Functions returning tuples in Swift - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this Swift function returning a tuple?

Consider the following Swift function that returns a tuple. What will be printed when calling result?

Swift

func getCoordinates() -> (x: Int, y: Int) {
    return (x: 10, y: 20)
}

let result = getCoordinates()
print("x: \(result.x), y: \(result.y)")

A x: 0, y: 0

B x: 20, y: 10

C x: 10 y: 20

D x: 10, y: 20

💡 Hint

Look at the tuple labels and values returned by the function.

The function returns a tuple with x = 10 and y = 20. Accessing result.x and result.y prints those values exactly.

🧠 Conceptual

intermediate

What is the type of the tuple returned by this function?

Given this Swift function, what is the exact type of the returned tuple?

Swift

func getUserInfo() -> (name: String, age: Int) {
    return (name: "Alice", age: 30)
}

A (name: String, age: Int)

B (String, Int)

C (String, String)

D (Int, String)

💡 Hint

Check if the tuple has labels or not.

The function returns a tuple with labels 'name' and 'age' of types String and Int respectively, so the type includes labels.

🔧 Debug

advanced

Why does this Swift function cause a compile error?

Examine the function below. Why does it cause a compile error?

Swift

func calculate() -> (Int, Int) {
    return (x: 5, y: 10)
}

A The tuple values are not integers

B The function is missing a return statement

C The return tuple has labels but the function return type does not specify labels

D The function return type must be a class, not a tuple

💡 Hint

Check if tuple labels in return match the declared return type.

The function return type is an unlabeled tuple (Int, Int), but the return statement uses labeled tuple (x: 5, y: 10). This mismatch causes a compile error.

❓ Predict Output

advanced

What is the output of this function returning multiple values as a tuple?

What will be printed when running this Swift code?

Swift

func minMax(numbers: [Int]) -> (min: Int, max: Int)? {
    guard let first = numbers.first else { return nil }
    var currentMin = first
    var currentMax = first
    for number in numbers {
        if number < currentMin {
            currentMin = number
        } else if number > currentMax {
            currentMax = number
        }
    }
    return (min: currentMin, max: currentMax)
}

if let result = minMax(numbers: [3, 7, 2, 9, 4]) {
    print("Min is \(result.min), Max is \(result.max)")
} else {
    print("Empty array")
}

A Min is 2, Max is 9

B Min is 3, Max is 7

C Min is 9, Max is 2

D Empty array

💡 Hint

The function finds the smallest and largest numbers in the array.

The smallest number in the array is 2 and the largest is 9, so the output prints those values.

🧠 Conceptual

expert

How can you access tuple elements returned by a Swift function without using labels?

Given a Swift function that returns an unlabeled tuple, how do you access the elements?

Swift

func getValues() -> (Int, String) {
    return (42, "Answer")
}

let values = getValues()

A Use values[0] and values[1]

B Use values.0 for the first element and values.1 for the second element

C Use values.first and values.second

D Use values.x and values.y

💡 Hint

Unlabeled tuples use numeric indices starting at zero.

Unlabeled tuple elements are accessed by .0, .1, etc. Using .first or subscripts is invalid for tuples.