Return Values

// BASIC RETURN VALUE
func add(a: Int, b: Int) -> Int {
    return a + b
}
let result = add(a: 5, b: 3)
print(result)  // 8

// IMPLICIT RETURN (single expression)
func multiply(a: Int, b: Int) -> Int {
    a * b  // No 'return' needed!
}

// RETURNING DIFFERENT TYPES
func isEven(_ number: Int) -> Bool {
    return number % 2 == 0
}

func greeting(for name: String) -> String {
    return "Hello, \(name)!"
}

// RETURNING OPTIONALS
func findIndex(of value: Int, in array: [Int]) -> Int? {
    for (index, element) in array.enumerated() {
        if element == value {
            return index
        }
    }
    return nil  // Not found
}

let numbers = [10, 20, 30, 40]
if let index = findIndex(of: 30, in: numbers) {
    print("Found at index \(index)")
}

// RETURNING TUPLES (multiple values!)
func minMax(array: [Int]) -> (min: Int, max: Int) {
    var min = array[0]
    var max = array[0]
    for value in array {
        if value < min { min = value }
        if value > max { max = value }
    }
    return (min, max)
}

let bounds = minMax(array: [5, 2, 8, 1, 9])
print("Min: \(bounds.min), Max: \(bounds.max)")

// OPTIONAL TUPLE RETURN
func minMax2(array: [Int]) -> (min: Int, max: Int)? {
    if array.isEmpty { return nil }
    return (array.min()!, array.max()!)
}

// EARLY RETURN WITH GUARD
func divide(_ a: Int, by b: Int) -> Int? {
    guard b != 0 else {
        print("Cannot divide by zero!")
        return nil
    }
    return a / b
}

// NEVER RETURNING (crashes or infinite loop)
func fatalError(_ message: String) -> Never {
    print(message)
    // This function never returns
}