func multiply(a: Int, b: Int) -> Int {
  return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return (a % 10) * (b % 10)
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return (a % 10) * (b % 10)
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<bos><start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<bos><start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<bos><start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<bos><start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<bos><start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<bos><start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<bos><start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<bos><start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<bos><start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<bos><start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    return abs(a % 10) * abs(b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return abs(a % 10) * abs(b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return abs(a % 10) * abs(b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return abs(a % 10) * abs(b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return abs(a % 10) * abs(b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return abs(a % 10) * abs(b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return abs(a) * abs(b)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return abs(a) * abs(b)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return abs(a % 10) * abs(b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return abs(a % 10) * abs(b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return abs(a % 10) * abs(b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return abs(a % 10) * abs(b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
  return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitA = a % 10
    let unitB = b % 10
    return (unitA * unitB) % 10
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitA = a % 10
    let unitB = b % 10
    return (unitA * unitB) % 10
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return (aUnitDigit * bUnitDigit) % 10
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return (aUnitDigit * bUnitDigit) % 10
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

import Foundation

func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

```swift
import Foundation

/* 
 Function to multiply two matrices represented as 2D arrays of Doubles.
 Returns a new matrix that is the product of `lhs` and `rhs`, or `nil` if the matrices cannot be multiplied.
 */
func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

/*
 Complete the function that takes two integers and returns 
 the product of their unit digits.
 Assume the input is always valid.
 Examples:
 multiply(a: 148, b: 412) == 16
 multiply(a: 19, b: 28) == 72
 multiply(a: 2020, b: 1851) == 0
 multiply(a: 14, b: -15) == 20
 */
func multiply(a: Int, b: Int) -> Int {

import Foundation

func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

```swift
import Foundation

/* 
 Function to multiply two matrices represented as 2D arrays of Doubles.
 Returns a new matrix that is the product of `lhs` and `rhs`, or `nil` if the matrices cannot be multiplied.
 */
func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

/*
 Complete the function that takes two integers and returns 
 the product of their unit digits.
 Assume the input is always valid.
 Examples:
 multiply(a: 148, b: 412) == 16
 multiply(a: 19, b: 28) == 72
 multiply(a: 2020, b: 1851) == 0
 multiply(a: 14, b: -15) == 20
 */
func multiply(a: Int, b: Int) -> Int {
    

import Foundation

func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

```swift
import Foundation

/* 
 Function to multiply two matrices represented as 2D arrays of Doubles.
 Returns a new matrix that is the product of `lhs` and `rhs`, or `nil` if the matrices cannot be multiplied.
 */
func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

/*
 Complete the function that takes two integers and returns 
 the product of their unit digits.
 Assume the input is always valid.
 Examples:
 multiply(a: 148, b: 412) == 16
 multiply(a: 19, b: 28) == 72
 multiply(a: 2020, b: 1851) == 0
 multiply(a: 14, b: -15) == 20
 */
func multiply(a: Int, b: Int) -> Int {
    
    
    

import Foundation

func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

```swift
import Foundation

/* 
 Function to multiply two matrices represented as 2D arrays of Doubles.
 Returns a new matrix that is the product of `lhs` and `rhs`, or `nil` if the matrices cannot be multiplied.
 */
func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

/*
 Complete the function that takes two integers and returns 
 the product of their unit digits.
 Assume the input is always valid.
 Examples:
 multiply(a: 148, b: 412) == 16
 multiply(a: 19, b: 28) == 72
 multiply(a: 2020, b: 1851) == 0
 multiply(a: 14, b: -15) == 20
 */
func multiply(a: Int, b: Int) -> Int {
    
    
    
    
    
    guard a

import Foundation

func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

```swift
import Foundation

/* 
 Function to multiply two matrices represented as 2D arrays of Doubles.
 Returns a new matrix that is the product of `lhs` and `rhs`, or `nil` if the matrices cannot be multiplied.
 */
func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

/*
 Complete the function that takes two integers and returns 
 the product of their unit digits.
 Assume the input is always valid.
 Examples:
 multiply(a: 148, b: 412) == 16
 multiply(a: 19, b: 28) == 72
 multiply(a: 2020, b: 1851) == 0
 multiply(a: 14, b: -15) == 20
 */
func multiply(a: Int, b: Int) -> Int {
    

import Foundation

func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

```swift
import Foundation

/* 
 Function to multiply two matrices represented as 2D arrays of Doubles.
 Returns a new matrix that is the product of `lhs` and `rhs`, or `nil` if the matrices cannot be multiplied.
 */
func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

/*
 Complete the function that takes two integers and returns 
 the product of their unit digits.
 Assume the input is always valid.
 Examples:
 multiply(a: 148, b: 412) == 16
 multiply(a: 19, b: 28) == 72
 multiply(a: 2020, b: 1851) == 0
 multiply(a: 14, b: -15) == 20
 */
func multiply(a: Int, b: Int) -> Int {
    
    
    
    

import Foundation

func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

```swift
import Foundation

/* 
 Function to multiply two matrices represented as 2D arrays of Doubles.
 Returns a new matrix that is the product of `lhs` and `rhs`, or `nil` if the matrices cannot be multiplied.
 */
func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

/*
 Complete the function that takes two integers and returns 
 the product of their unit digits.
 Assume the input is always valid.
 Examples:
 multiply(a: 148, b: 412) == 16
 multiply(a: 19, b: 28) == 72
 multiply(a: 2020, b: 1851) == 0
 multiply(a: 14, b: -15) == 20
 */
func multiply(a: Int, b: Int) -> Int {
    
    
    

import Foundation

func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

```swift
import Foundation

/* 
 Function to multiply two matrices represented as 2D arrays of Doubles.
 Returns a new matrix that is the product of `lhs` and `rhs`, or `nil` if the matrices cannot be multiplied.
 */
func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

/*
 Complete the function that takes two integers and returns 
 the product of their unit digits.
 Assume the input is always valid.
 Examples:
 multiply(a: 148, b: 412) == 16
 multiply(a: 19, b: 28) == 72
 multiply(a: 2020, b: 1851) == 0
 multiply(a: 14, b: -15) == 20
 */
func multiply(a: Int, b: Int) -> Int {
    
    
    
    
    guard a = multiply(l

import Foundation

func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

```swift
import Foundation

/* 
 Function to multiply two matrices represented as 2D arrays of Doubles.
 Returns a new matrix that is the product of `lhs` and `rhs`, or `nil` if the matrices cannot be multiplied.
 */
func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

/*
 Complete the function that takes two integers and returns 
 the product of their unit digits.
 Assume the input is always valid.
 Examples:
 multiply(a: 148, b: 412) == 16
 multiply(a: 19, b: 28) == 72
 multiply(a: 2020, b: 1851) == 0
 multiply(a: 14, b: -15) == 20
 */
func multiply(a: Int, b: Int) -> Int {
    
    
    
    

import Foundation

func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

```swift
import Foundation

/* 
 Function to multiply two matrices represented as 2D arrays of Doubles.
 Returns a new matrix that is the product of `lhs` and `rhs`, or `nil` if the matrices cannot be multiplied.
 */
func multiply(_ lhs: [[Double]], _ rhs: [[Double]]) -> [[Double]]? {
    guard lhs[0].count == rhs.count else { 
        return nil 
    }
    
    var result = [[Double]](repeating: [Double](repeating: 0, count: rhs[0].count), count: lhs.count)
    for i in 0..<lhs.count {
        for j in 0..<rhs[0].count {
            for k in 0..<rhs.count {
                result[i][j] += lhs[i][k] * rhs[k][j]
            }
        }
    }
    
    return result
}

/*
 Complete the function that takes two integers and returns 
 the product of their unit digits.
 Assume the input is always valid.
 Examples:
 multiply(a: 148, b: 412) == 16
 multiply(a: 19, b: 28) == 72
 multiply(a: 2020, b: 1851) == 0
 multiply(a: 14, b: -15) == 20
 */
func multiply(a: Int, b: Int) -> Int {
    
    
    
    
    var

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
Here's because the product of unit digits of unit digits of unit digits is 1 and 4 and 4 and 1 and 4 and 1 and 2 and

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
Here is to getUnitDigit(a: Int {
    let unitDigitsUnitProduct(a: Int {
        let unit

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {

Here is the function getUnitDigitself.productOfUnitDig

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
Here's because the product of unit digits of unit digits are 1*

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {

Here is because the product

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
Here is the complete function:

```

func multiply(a: Int, b: Int) -> Int {
    var result = 0
    var a = abs(a)
    var b = abs(b)
    
    while b > 0 {
        if b % 2 != 0 {
            result += a
        }
        a *= 2
        b /= 2
    }
    
    return result
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    var result = 0
    var a = abs(a)
    var b = abs(b)
    
    while b > 0 {
        if b % 2 != 0 {
            result += a
        }
        a *= 2
        b /= 2
    }
    
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    let aDigits = a.abs().map { Int(String($0))! }
    let bDigits = b.abs().map { Int(String($0))! }
    
    var result = 0
    for aDigit in aDigits {
        for bDigit in bDigits {
            result += aDigit * bDigit
        }
    }
    
    return result
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aDigits = a.abs().map { Int(String($0))! }
    let bDigits = b.abs().map { Int(String($0))! }
    
    var result = 0
    for aDigit in aDigits {
        for bDigit in bDigits {
            result += aDigit * bDigit
        }
    }
    
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    
    while a != 0 || b != 0 {
        if a % 10 != 0 {
            product *= a % 10
        }
        a /= 10
        
        if b % 10 != 0 {
            product *= b % 10
        }
        b /= 10
    }
    
    return product
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    
    while a != 0 || b != 0 {
        if a % 10 != 0 {
            product *= a % 10
        }
        a /= 10
        
        if b % 10 != 0 {
            product *= b % 10
        }
        b /= 10
    }
    
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    var negative = false
    
    if a < 0 {
        a = -a
        negative = !negative
    }
    if b < 0 {
        b = -b
        negative = !negative
    }
    
    while a > 0 {
        if a % 10 != 0 {
            product *= a % 10
        }
        a /= 10
    }
    
    while b > 0 {
        if b % 10 != 0 {
            product *= b % 10
        }
        b /= 10
    }
    
    if negative {
        product = -product
    }
    
    return product
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    var negative = false
    
    if a < 0 {
        a = -a
        negative = !negative
    }
    if b < 0 {
        b = -b
        negative = !negative
    }
    
    while a > 0 {
        if a % 10 != 0 {
            product *= a % 10
        }
        a /= 10
    }
    
    while b > 0 {
        if b % 10 != 0 {
            product *= b % 10
        }
        b /= 10
    }
    
    if negative {
        product = -product
    }
    
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aDigits = a.abs().map { Int(String($0))! }
    let bDigits = b.abs().map { Int(String($0))! }
    
    let aProduct = aDigits.reduce(0, { $0 * $1 })
    let bProduct = bDigits.reduce(0, { $0 * $1 })
    
    return aProduct * bProduct
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aDigits = a.abs().map { Int(String($0))! }
    let bDigits = b.abs().map { Int(String($0))! }
    
    let aProduct = aDigits.reduce(0, { $0 * $1 })
    let bProduct = bDigits.reduce(0, { $0 * $1 })
    
    return aProduct * bProduct
}
```

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    while a != 0 || b != 0 {
        if a % 10 != 0 {
            product *= a % 10
        }
        a /= 10
        if b % 10 != 0 {
            product *= b % 10
        }
        b /= 10
    }
    return product
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    while a != 0 || b != 0 {
        if a % 10 != 0 {
            product *= a % 10
        }
        a /= 10
        if b % 10 != 0 {
            product *= b % 10
        }
        b /= 10
    }
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let product = a * b
    var productDigits = [Int]()
    var sign = (a > 0) == (b > 0) ? 1 : -1
    a = abs(a)
    b = abs(b)
    while a > 0 || b > 0 {
        if a % 10 != 0 || b % 10 != 0 {
            productDigits.append((a % 10) * (b % 10))
        }
        a /= 10
        b /= 10
    }
    var result = 0
    var mul = 1
    for i in productDigits.reversed() {
        result += mul * i
        mul *= 10
    }
    return result * sign
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let product = a * b
    var productDigits = [Int]()
    var sign = (a > 0) == (b > 0) ? 1 : -1
    a = abs(a)
    b = abs(b)
    while a > 0 || b > 0 {
        if a % 10 != 0 || b % 10 != 0 {
            productDigits.append((a % 10) * (b % 10))
        }
        a /= 10
        b /= 10
    }
    var result = 0
    var mul = 1
    for i in productDigits.reversed() {
        result += mul * i
        mul *= 10
    }
    return result * sign
}
```

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    
    while a > 0 || b > 0 {
        if a % 10 > 0 {
            product *= a % 10
        }
        a /= 10
        
        if b % 10 > 0 {
            product *= b % 10
        }
        b /= 10
    }
    
    return product
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    
    while a > 0 || b > 0 {
        if a % 10 > 0 {
            product *= a % 10
        }
        a /= 10
        
        if b % 10 > 0 {
            product *= b % 10
        }
        b /= 10
    }
    
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aDigits = a.abs().map { Int(String($0))! }
    let bDigits = b.abs().map { Int(String($0))! }
    
    let aProduct = aDigits.reduce(0, { $0 + $1 * (a % 10) })
    let bProduct = bDigits.reduce(0, { $0 + $1 * (b % 10) })
    
    return aProduct * bProduct
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aDigits = a.abs().map { Int(String($0))! }
    let bDigits = b.abs().map { Int(String($0))! }
    
    let aProduct = aDigits.reduce(0, { $0 + $1 * (a % 10) })
    let bProduct = bDigits.reduce(0, { $0 + $1 * (b % 10) })
    
    return aProduct * bProduct
}
```

func multiply(a: Int, b: Int) -> Int {
    let product = a * b
    var productDigits = [Int]()
    var digit: Int
    var negative = false
    
    if product < 0 {
        negative = true
        product *= -1
    }
    
    while product > 0 {
        digit = product % 10
        productDigits.append(digit)
        product /= 10
    }
    
    var result = 1
    for digit in productDigits {
        result *= digit
    }
    
    if negative {
        result *= -1
    }
    
    return result
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let product = a * b
    var productDigits = [Int]()
    var digit: Int
    var negative = false
    
    if product < 0 {
        negative = true
        product *= -1
    }
    
    while product > 0 {
        digit = product % 10
        productDigits.append(digit)
        product /= 10
    }
    
    var result = 1
    for digit in productDigits {
        result *= digit
    }
    
    if negative {
        result *= -1
    }
    
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = abs(a) % 10
    let bLastDigit = abs(b) % 10
    return aLastDigit * bLastDigit
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = abs(a) % 10
    let bLastDigit = abs(b) % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = abs(a) % 10
    let bLastDigit = abs(b) % 10
    return aLastDigit * bLastDigit
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = abs(a) % 10
    let bLastDigit = abs(b) % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = abs(a) % 10
    let bLastDigit = abs(b) % 10
    return aLastDigit * bLastDigit
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aLastDigit = abs(a) % 10
    let bLastDigit = abs(b) % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

<｜begin▁of▁sentence｜>You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
import Foundation

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let first = a % 10
    let second = b % 10
    return first * second
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let first = a % 10
    let second = b % 10
    return first * second
}
```

func multiply(a: Int, b: Int) -> Int {
    let first = a % 10
    let second = b % 10
    return first * second
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let first = a % 10
    let second = b % 10
    return first * second
}
```

func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}
```

func multiply(a: Int, b: Int) -> Int {
    let a1 = a % 10
    let b1 = b % 10
    return a1 * b1
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a1 = a % 10
    let b1 = b % 10
    return a1 * b1
}
```

func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}
```

func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}
```

func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}
```

func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}
```

func multiply(a: Int, b: Int) -> Int {
    let first = a % 10
    let second = b % 10
    return first * second
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let first = a % 10
    let second = b % 10
    return first * second
}
```

func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}
```

func multiply(a: Int, b: Int) -> Int {
    // TODO: Complete this function
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // TODO: Complete this function
}
```

func multiply(a: Int, b: Int) -> Int {
    var result = 0
    var a_unit = a % 10
    var b_unit = b % 10
    
    while b > 0 {
        if b % 2 == 1 {
            result += a_unit
        }
        a_unit *= 2
        b /= 2
    }
    
    return result
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    var result = 0
    var a_unit = a % 10
    var b_unit = b % 10
    
    while b > 0 {
        if b % 2 == 1 {
            result += a_unit
        }
        a_unit *= 2
        b /= 2
    }
    
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    // Write your code here
    var result = 0
    var a = a
    var b = b
    while b > 0 {
        if b & 1 == 1 {
            result += a
        }
        a <<= 1
        b >>= 1
    }
    return result
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // Write your code here
    var result = 0
    var a = a
    var b = b
    while b > 0 {
        if b & 1 == 1 {
            result += a
        }
        a <<= 1
        b >>= 1
    }
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    // Write your code here
    var a = a
    var b = b
    var result = 0
    
    while b > 0 {
        if b % 2 == 1 {
            result += a
        }
        a = a << 1
        b = b >> 1
    }
    
    return result
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // Write your code here
    var a = a
    var b = b
    var result = 0
    
    while b > 0 {
        if b % 2 == 1 {
            result += a
        }
        a = a << 1
        b = b >> 1
    }
    
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    // TODO: Implement this function
    
    // Your code here
    
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // TODO: Implement this function
    
    // Your code here
    
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    // TODO: Implement this function
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // TODO: Implement this function
}
```

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // TODO: Implement this function.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use the built-in functions from Swift.
    // You can use

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var result = 0
    while b > 0 {
        if b & 1 == 1 {
            result += a
        }
        a <<= 1
        b >>= 1
    }
    return result
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var result = 0
    while b > 0 {
        if b & 1 == 1 {
            result += a
        }
        a <<= 1
        b >>= 1
    }
    return result
}
```

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // Write your code here
    
    // 先把 a 和 b 的各位数字拿出来
    var a_unit_digits = a
    var b_unit_digits = b
    
    // 然后把 a 和 b 的各位数字拿出来
    var a_unit_digits_array = []
    var b_unit_digits_array = []
    
    while a_unit_digits > 0 {
        a_unit_digits_array.append(a_unit_digits % 10)
        a_unit_digits /= 10
    }
    
    while b_unit_digits > 0 {
        b_unit_digits_array.append(b_unit_digits % 10)
        b_unit_digits /= 10
    }
    
    // 然后把 a 和 b 的各位数字拿出来
    var a_unit_digits_array_reversed = []
    var b_unit_digits_array_reversed = []
    
    for i in a_unit_digits_array.reversed() {
        a_unit_digits_array_reversed.append(i)
    }
    
    for i in b_unit_digits_array.reversed() {
        b_unit_digits_array_reversed.append(i)
    }
    
    // 然后把 a 和 b 的各位数字拿出来
    var a_unit_digits_array_reversed_product = 1
    var b_unit_digits_array_reversed_product = 1
    
    for i in a_unit_digits_array_reversed {
        a_unit_digits_array_reversed_product *= i
    }
    
    for i in b_unit_digits_array_reversed {
        b_unit_digits_array_reversed_product *= i
    }
    
    // 然后把 a 和 b 的各位数字拿出来
    var a_unit_digits_array_reversed_product_array = []
    var b_unit_digits_array_reversed_product_array = []
    
    while a_unit_digits_array_reversed_product > 0 {
        a_unit_digits_array_reversed_product_array.append(a_unit_digits_array_reversed_product % 10)
        a_unit_digits_array_reversed_product /= 10
    }
    
    while b_unit_digits_array_reversed_product > 0 {
        b_unit_digits_array_reversed_product_array.append(b_unit_digits_array_reversed_product % 10)
        b_unit_digits_array_reversed_product /= 10
    }
    
    // 然后把 a 和 b 的各位数字拿出来
    var a_unit_digits_array_reversed_product_array_reversed = []
    var b_unit_digits_array_reversed_product_array_reversed = []
    
    for i in a_unit_digits_array_reversed_product_array.reversed() {
        a_unit_digits_array_reversed_product_array_reversed.append(i)
    }
    
    for i in b_unit_digits_array_reversed_product_array.reversed() {
        b_unit_digits_array_reversed_product_array_reversed.append(i)
    }
    
    // 然后把 a 和 b 的各位数字拿出来
    var a_unit_digits_array_reversed_product_array_reversed_product = 1
    var b_unit_digits_array_reversed_product_array_reversed_product = 1
    
    for i in a_unit_digits_array_reversed_product_array_reversed {
        a_unit_digits_array_reversed_product_array_reversed_product *= i
    }
    
    for i in b_unit_dig

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var result = 0
    
    while b > 0 {
        if b & 1 == 1 {
            result += a
        }
        a <<= 1
        b >>= 1
    }
    
    return result
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var result = 0
    
    while b > 0 {
        if b & 1 == 1 {
            result += a
        }
        a <<= 1
        b >>= 1
    }
    
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<|im_end|>
<|im_start|>assistant
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```
### Problem

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```
### Problem

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```
### Test

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let a = abs(a)
    let b = abs(b)
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}

### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let a = abs(a)
    let b = abs(b)
    let aLastDigit = a % 10
    let bLastDigit = b % 10
    return aLastDigit * bLastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    // Get the units digit of each number
    let unitDigitA = A % 10
    let unitDigitB = b % 10
    
    // Multiply the unit digits
    let product = unitDigitA * unitDigitB
    
    return product
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // Get the units digit of each number
    let unitDigitA = A % 10
    let unitDigitB = b % 10
    
    // Multiply the unit digits
    let product = unitDigitA * unitDigitB
    
    return product
}

// Example usage:
print(multiply(A: 148, b: 412))  // Output: 16
print(multiply(A: 19, b: 28))    // Output: 72
print(multiply(A: 2020, b: 1851))// Output: 0
print(multiply(A: 14, b: -15))   // Output: 20
```

func multiply(a: Int, b: Int) -> Int {
    // your code here
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // your code here
}
```

func multiply(a: Int, b: Int) -> Int {
    // your code here
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // your code here
}
```

func multiply(a: Int, b: Int) -> Int {
    // your code here
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // your code here
}
```

func multiply(a: Int, b: Int) -> Int {
    // your code here
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // your code here
}
```

func multiply(a: Int, b: Int) -> Int {
    // your code here
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // your code here
}
```

func multiply(a: Int, b: Int) -> Int {
    // your code here
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // your code here
}
```

func multiply(a: Int, b: Int) -> Int {
    // your code here!
    let a = String(A)
    let B = String(B)
    let A = A[A.index(A.endIndex, offsetBy: -1)]
    let B = B[B.index(B.endIndex, offsetBy: -1)]
    return Int(A) * Int(B)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // your code here!
    let a = String(A)
    let B = String(B)
    let A = A[A.index(A.endIndex, offsetBy: -1)]
    let B = B[B.index(B.endIndex, offsetBy: -1)]
    return Int(A) * Int(B)
}
```

func multiply(a: Int, b: Int) -> Int {
    // your code here
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // your code here
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    // Your code here
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // Your code here
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
    return abs(a) * abs(b)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return abs(a) * abs(b)
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

func powersOfTwo(n: Int) -> [Int] {
    var result = [Int]()
    for i in 0...n {
        result.append(2^i)
    }
    return result
}

func fakeBin(x: String) -> String {
    var result = ""
    for i in x {
        if Int(String(i))! < 5 {
            result += "0"
        } else {
            result += "1"
        }
    }
    return result
}

func grow(arr: [Int]) -> Int {
    var result = 1
    for i in arr {
        result *= i
    }
    return result
}

func maps(x: [Int]) -> [Int] {
    var result = [Int]()
    for i in x {
        result.append(i * 2)
    }
    return result
}

func sumArray(array: [Double]) -> Double {
    var result = 0.0
    for i in array {
        result += i
    }
    return result
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}

// Complete the function that takes a non-negative integer n as input, and returns a list of all the powers of 2 with the exponent ranging from 0 to n ( inclusive ).
// Examples
// n = 0  ==> [1]        # [2^0]
// n = 1  ==> [1, 2]     # [2^0, 2^1]
// n = 2  ==> [1, 2, 4]  # [2^0, 2^1, 2^2]
func powersOfTwo(n: Int) -> [Int] {
    var result = [Int]()
    for i in 0...n {
        result.append(2^i)
    }
    return result
}

// Given a string of digits, you should replace any digit below 5 with '0' and any digit 5 and above with '1'. Return the resulting string.
// Note: input will never be an empty string
func fakeBin(x: String) -> String {
    var result = ""
    for i in x {
        if Int(String(i))! < 5 {
            result += "0"
        } else {
            result += "1"
        }
    }
    return result
}

// Given a non-empty array of integers, return the result of multiplying the values together in order. Example:
// [1, 2, 3, 4] => 1 * 2 * 3 * 4 = 24
func grow(arr: [Int]) -> Int {
    var result = 1
    for i in arr {
        result *= i
    }
    return result
}

// Given an array of integers, return a new array with each value doubled.
// For example:
// [1, 2, 3] --> [2, 4, 6]
func maps(x: [Int]) -> [Int] {
    var result = [Int]()
    for i in x {
        result.append(i * 2)
    }
    return result
}

// Write a function that takes an array of numbers and returns the sum of the numbers. The numbers can be negative or non-integer. If the array does not contain any numbers then you should return 0.
// Examples
// Input: [1, 5.2, 4, 0, -1]
// Output: 9.2
// Input: []
// Output: 0
// Input: [-2.398]
// Output: -2.398
// Assumptions
// You can assume that you are only given numbers.
// You cannot assume the size of the array.
// You can assume that you do get an array and if the array is empty, return 0.
// What We're Testing
// We're testing basic loops and math operations. This is for beginners who are just learning loops and math operations.
// Advanced users may find this extremely easy and can easily write this in one line.
func sumArray(array: [Double]) -> Double {
    var result = 0.0
    for i in array {
        result += i
    }
    return result
}

// Given an array of integers, return a new array with each value doubled.
// For example:
// [1, 2, 3] --> [2, 4, 6]
func maps(x: [Int]) -> [Int] {
    var result = [Int]()
    for i in x {
        result.append(i * 2)
    }
    return result
}

// Given an array of integers, return a new array with each value doubled.
// For example:
// [1, 2, 3] --> [2, 4, 6]
func maps(x: [Int]) -> [Int] {
    var result = [Int]()
    for i in x {
        result.append(i * 2)
    }
    return result
}

// Given an array of integers, return a new array with each value doubled.
// For example:
// [1, 2, 3] --> [2, 4, 6]
func maps(x: [Int]) -> [Int] {
    var result = [Int]()
    for i in x {
        result.append(i * 2)
    }
    return result
}

// Given an array of integers, return a new array with each value doubled

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>```

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
  return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return a * b
}
<|file_separator|>```

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}
<|file_separator|>

func multiply(a: Int, b: Int) -> Int {
    let a = String(a)
    let b = String(b)
    let a = a.suffix(1)
    let b = b.suffix(1)
    let a = a.prefix(1)
    let b = b.prefix(1)
    let a = String(a)
    let b = String(b)
    let a = Int(a)!
    let b = Int(b)!
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a = String(a)
    let b = String(b)
    let a = a.suffix(1)
    let b = b.suffix(1)
    let a = a.prefix(1)
    let b = b.prefix(1)
    let a = String(a)
    let b = String(b)
    let a = Int(a)!
    let b = Int(b)!
    return a * b
}
```

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var result = 1
    while a != 0 || b != 0 {
        result *= (a % 10) * (b % 10)
        a /= 10
        b /= 10
    }
    return result
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var result = 1
    while a != 0 || b != 0 {
        result *= (a % 10) * (b % 10)
        a /= 10
        b /= 10
    }
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let a1 = a % 10
    let b1 = b % 10
    return a1 * b1
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a1 = a % 10
    let b1 = b % 10
    return a1 * b1
}
```

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var result = 0
    while a > 0 || b > 0 {
        let aUnit = a % 10
        let bUnit = b % 10
        result += aUnit * bUnit
        a = a / 10
        b = b / 10
    }
    return result
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var result = 0
    while a > 0 || b > 0 {
        let aUnit = a % 10
        let bUnit = b % 10
        result += aUnit * bUnit
        a = a / 10
        b = b / 10
    }
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    var result = 0
    var a = a.absoluteValue
    var b = b.absoluteValue
    var aDigits = a.digits
    var bDigits = b.digits
    for i in 0..<aDigits.count {
        for j in 0..<bDigits.count {
            result += aDigits[i] * bDigits[j] * 10.0.pow((aDigits.count - i - 1) + (bDigits.count - j - 1))
        }
    }
    return result
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    var result = 0
    var a = a.absoluteValue
    var b = b.absoluteValue
    var aDigits = a.digits
    var bDigits = b.digits
    for i in 0..<aDigits.count {
        for j in 0..<bDigits.count {
            result += aDigits[i] * bDigits[j] * 10.0.pow((aDigits.count - i - 1) + (bDigits.count - j - 1))
        }
    }
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    var result = 0
    var aStr = a.toString()
    var bStr = b.toString()
    for i in 0..<aStr.count {
        for j in 0..<bStr.count {
            result += (aStr[i] - '0') * (bStr[j] - '0') * 10.0.pow((aStr.count - i - 1) + (bStr.count - j - 1))
        }
    }
    return result
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    var result = 0
    var aStr = a.toString()
    var bStr = b.toString()
    for i in 0..<aStr.count {
        for j in 0..<bStr.count {
            result += (aStr[i] - '0') * (bStr[j] - '0') * 10.0.pow((aStr.count - i - 1) + (bStr.count - j - 1))
        }
    }
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    let a_unit_digit = a % 10;
    let b_unit_digit = b % 10;
    return a_unit_digit * b_unit_digit;
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a_unit_digit = a % 10;
    let b_unit_digit = b % 10;
    return a_unit_digit * b_unit_digit;
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let a_unit_digit = a % 10;
    let b_unit_digit = b % 10;
    return a_unit_digit * b_unit_digit;
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a_unit_digit = a % 10;
    let b_unit_digit = b % 10;
    return a_unit_digit * b_unit_digit;
}
```

func multiply(a: Int, b: Int) -> Int {
    let a_unit_digit = a % 10
    let b_unit_digit = b % 10
    return a_unit_digit * b_unit_digit
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a_unit_digit = a % 10
    let b_unit_digit = b % 10
    return a_unit_digit * b_unit_digit
}
```

func multiply(a: Int, b: Int) -> Int {
    var a1 = a % 10
    var a2 = (a - a1) / 10
    var b1 = b % 10
    var b2 = (b - b1) / 10
    return a1 * b1 + (a2 * b1) + (a1 * b2) + (a2 * b2)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    var a1 = a % 10
    var a2 = (a - a1) / 10
    var b1 = b % 10
    var b2 = (b - b1) / 10
    return a1 * b1 + (a2 * b1) + (a1 * b2) + (a2 * b2)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let a_unit_digit = a % 10
    let b_unit_digit = b % 10
    return a_unit_digit * b_unit_digit
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a_unit_digit = a % 10
    let b_unit_digit = b % 10
    return a_unit_digit * b_unit_digit
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnit = a % 10
    let bUnit = b % 10
    return aUnit * bUnit
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

<start_of_turn>user
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20<end_of_turn>
<start_of_turn>model
```swift
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitsA = a % 10
    let unitDigitsB = b % 10
    return unitDigitsA * unitDigitsB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitsA = a % 10
    let unitDigitsB = b % 10
    return unitDigitsA * unitDigitsB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitsA = a % 10
    let unitDigitsB = b % 10
    return unitDigitsA * unitDigitsB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitsA = a % 10
    let unitDigitsB = b % 10
    return unitDigitsA * unitDigitsB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitsA = a % 10
    let unitDigitsB = b % 10
    return unitDigitsA * unitDigitsB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitsA = a % 10
    let unitDigitsB = b % 10
    return unitDigitsA * unitDigitsB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigits = [a % 10, b % 10]
    return unitDigits.reduce(1, *)
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigits = [a % 10, b % 10]
    return unitDigits.reduce(1, *)
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigits = [a % 10, b % 10]
    return unitDigits.reduce(1, *)
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigits = [a % 10, b % 10]
    return unitDigits.reduce(1, *)
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigits = [a % 10, b % 10]
    return unitDigits.reduce(1, *)
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigits = [a % 10, b % 10]
    return unitDigits.reduce(1, *)
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

[INST] Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20 [/INST] ```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = a % 10
    let unitDigitB = b % 10
    return (unitDigitA * unitDigitB) % 10
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}

Question:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20

Answer:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = a % 10
    let bUnitDigit = b % 10
    let product = aUnitDigit * bUnitDigit
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let lastDigitA = abs(a % 10)
    let lastDigitB = abs(b % 10)
    return lastDigitA * lastDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aUnitDigit = abs(a % 10)
    let bUnitDigit = abs(b % 10)
    return aUnitDigit * bUnitDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let unitDigitA = abs(a % 10)
    let unitDigitB = abs(b % 10)
    return unitDigitA * unitDigitB
}
```

func multiply(a: Int, b: Int) -> Int {
    let aDigits = a.abs().map { Int(String($0))! }
    let bDigits = b.abs().map { Int(String($0))! }
    let aProduct = aDigits.reduce(0, { $0 + $1 })
    let bProduct = bDigits.reduce(0, { $0 + $1 })
    return aProduct * bProduct
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aDigits = a.abs().map { Int(String($0))! }
    let bDigits = b.abs().map { Int(String($0))! }
    let aProduct = aDigits.reduce(0, { $0 + $1 })
    let bProduct = bDigits.reduce(0, { $0 + $1 })
    return aProduct * bProduct
}
```

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    
    while a > 0 {
        if a % 10 != 0 {
            product *= a % 10
        }
        a /= 10
    }
    
    while b > 0 {
        if b % 10 != 0 {
            product *= b % 10
        }
        b /= 10
    }
    
    return product
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    
    while a > 0 {
        if a % 10 != 0 {
            product *= a % 10
        }
        a /= 10
    }
    
    while b > 0 {
        if b % 10 != 0 {
            product *= b % 10
        }
        b /= 10
    }
    
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    a = abs(a)
    b = abs(b)
    var product = 0
    for _ in 0..<a.countDigits() {
        product += b.multiply(by: a.popLast())
    }
    return product
}

func Int.countDigits() -> Int {
    var n = self
    var count = 0
    while n > 0 {
        n /= 10
        count += 1
    }
    return count
}

func Int.popLast() -> Int {
    var n = self
    var lastDigit = 0
    while n > 0 {
        lastDigit = n % 10
        n /= 10
    }
    return lastDigit
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    a = abs(a)
    b = abs(b)
    var product = 0
    for _ in 0..<a.countDigits() {
        product += b.multiply(by: a.popLast())
    }
    return product
}

func Int.countDigits() -> Int {
    var n = self
    var count = 0
    while n > 0 {
        n /= 10
        count += 1
    }
    return count
}

func Int.popLast() -> Int {
    var n = self
    var lastDigit = 0
    while n > 0 {
        lastDigit = n % 10
        n /= 10
    }
    return lastDigit
}
```

func multiply(a: Int, b: Int) -> Int {
    let aDigits = a.abs().map { Int(String($0))! }
    let bDigits = b.abs().map { Int(String($0))! }
    let aProduct = aDigits.reduce(0, { $0 + $1 })
    let bProduct = bDigits.reduce(0, { $0 + $1 })
    return aProduct * bProduct
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aDigits = a.abs().map { Int(String($0))! }
    let bDigits = b.abs().map { Int(String($0))! }
    let aProduct = aDigits.reduce(0, { $0 + $1 })
    let bProduct = bDigits.reduce(0, { $0 + $1 })
    return aProduct * bProduct
}
```

func multiply(a: Int, b: Int) -> Int {
    let aDigits = a.abs().map { Int(String($0))! }
    let bDigits = b.abs().map { Int(String($0))! }
    
    var result = 0
    for aDigit in aDigits {
        for bDigit in bDigits {
            result += aDigit * bDigit
        }
    }
    
    return result
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    let aDigits = a.abs().map { Int(String($0))! }
    let bDigits = b.abs().map { Int(String($0))! }
    
    var result = 0
    for aDigit in aDigits {
        for bDigit in bDigits {
            result += aDigit * bDigit
        }
    }
    
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    a = abs(a)
    b = abs(b)
    var product = 0
    for _ in 0..<a.description.count {
        product += b
    }
    return product
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    a = abs(a)
    b = abs(b)
    var product = 0
    for _ in 0..<a.description.count {
        product += b
    }
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    
    while a != 0 || b != 0 {
        if a % 10 != 0 {
            product *= a % 10
        }
        a /= 10
        
        if b % 10 != 0 {
            product *= b % 10
        }
        b /= 10
    }
    
    return product
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    
    while a != 0 || b != 0 {
        if a % 10 != 0 {
            product *= a % 10
        }
        a /= 10
        
        if b % 10 != 0 {
            product *= b % 10
        }
        b /= 10
    }
    
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    var negative = false
    
    if (a < 0 && b > 0) || (a > 0 && b < 0) {
        negative = true
    }
    
    a = abs(a)
    b = abs(b)
    
    while a > 0 {
        if a % 10 != 0 {
            product *= a % 10
        }
        a /= 10
    }
    
    while b > 0 {
        if b % 10 != 0 {
            product *= b % 10
        }
        b /= 10
    }
    
    if negative {
        product *= -1
    }
    
    return product
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    var a = a
    var b = b
    var product = 1
    var negative = false
    
    if (a < 0 && b > 0) || (a > 0 && b < 0) {
        negative = true
    }
    
    a = abs(a)
    b = abs(b)
    
    while a > 0 {
        if a % 10 != 0 {
            product *= a % 10
        }
        a /= 10
    }
    
    while b > 0 {
        if b % 10 != 0 {
            product *= b % 10
        }
        b /= 10
    }
    
    if negative {
        product *= -1
    }
    
    return product
}
```

func multiply(a: Int, b: Int) -> Int {
    var result = 0
    var a = abs(a)
    var b = abs(b)
    
    while b > 0 {
        if b % 2 != 0 {
            result += a
        }
        a *= 2
        b /= 2
    }
    
    return result
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    var result = 0
    var a = abs(a)
    var b = abs(b)
    
    while b > 0 {
        if b % 2 != 0 {
            result += a
        }
        a *= 2
        b /= 2
    }
    
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    var result = 0
    var a = abs(a)
    var b = abs(b)
    
    while b > 0 {
        if b % 2 != 0 {
            result += a
        }
        a *= 2
        b /= 2
    }
    
    return result
}

You are an AI programming assistant, utilizing the Deepseek Coder model, developed by Deepseek Company, and you only answer questions related to computer science. For politically sensitive questions, security and privacy issues, and other non-computer science questions, you will refuse to answer
### Instruction:
Write code in Swift programming language. Don't include usage examples or tests.
Complete the function that takes two integers and returns 
the product of their unit digits.
Assume the input is always valid.
Examples:
multiply(a: 148, b: 412) == 16
multiply(a: 19, b: 28) == 72
multiply(a: 2020, b: 1851) == 0
multiply(a: 14, b: -15) == 20
### Response:
```swift
func multiply(a: Int, b: Int) -> Int {
    var result = 0
    var a = abs(a)
    var b = abs(b)
    
    while b > 0 {
        if b % 2 != 0 {
            result += a
        }
        a *= 2
        b /= 2
    }
    
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return a * b
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
    return 0
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return 0
}
```

func multiply(a: Int, b: Int) -> Int {
  return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
  return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
  return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    let a = a % 10
    let b = b % 10
    return a * b
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    return (a % 10) * (b % 10)
}
```

func multiply(a: Int, b: Int) -> Int {
    // Write your code here
    var result = 0
    var a_unit = a % 10
    var b_unit = b % 10
    while b > 0 {
        if b % 2 == 1 {
            result += a_unit
        }
        a_unit *= 2
        b /= 2
    }
    return result
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // Write your code here
    var result = 0
    var a_unit = a % 10
    var b_unit = b % 10
    while b > 0 {
        if b % 2 == 1 {
            result += a_unit
        }
        a_unit *= 2
        b /= 2
    }
    return result
}
```

func multiply(a: Int, b: Int) -> Int {
    // TODO: Implement this function
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // TODO: Implement this function
}
```

func multiply(a: Int, b: Int) -> Int {
    // TODO: Complete this function
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // TODO: Complete this function
}
```

func multiply(a: Int, b: Int) -> Int {
    // TODO: Implement this function
}

```swift
// Complete the function that takes two integers and returns 
// the product of their unit digits.
// Assume the input is always valid.
// Examples:
// multiply(a: 148, b: 412) == 16
// multiply(a: 19, b: 28) == 72
// multiply(a: 2020, b: 1851) == 0
// multiply(a: 14, b: -15) == 20
func multiply(a: Int, b: Int) -> Int {
    // TODO: Implement this function
}
```