Programming Fundamentals/Functions/Swift

functions.swift

// This program asks the user for a Fahrenheit temperature, 
// converts the given temperature to Celsius,
// and displays the results.
//
// References:
//     https://www.mathsisfun.com/temperature-conversion.html
//     https://developer.apple.com/library/content/documentation/Swift/Conceptual/Swift_Programming_Language/TheBasics.html

func getFahrenheit() -> Double 
{
    var fahrenheit: Double
    
    print("Enter Fahrenheit temperature:")
    fahrenheit = Double(readLine(strippingNewline: true)!)!
    
    return fahrenheit
}

func calculateCelsius(fahrenheit: Double) -> Double 
{
    var celsius: Double
    
    celsius = (fahrenheit - 32) * 5 / 9
    
    return celsius
}

func displayResult(fahrenheit: Double, celsius: Double) 
{
    print(String(fahrenheit) + "° Fahrenheit is " + String(celsius) + "° Celsius")
}

func main()
{
    var fahrenheit: Double
    var celsius: Double
    
    fahrenheit = getFahrenheit()
    celsius = calculateCelsius(fahrenheit:fahrenheit)
    displayResult(fahrenheit:fahrenheit, celsius:celsius)
}

main()

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functions.swift

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