subtractTwoNumbers()

Step 1: Understanding the Problem

We are tasked with writing a Swift function that subtracts two numbers. Swift is a powerful and intuitive programming language developed by Apple for iOS, macOS, watchOS, and tvOS app development. It’s a safe, fast, and interactive programming language.

Step 2: Setting up the Function

First, let's declare our function. We know that our function will take two numbers as parameters. We'll call these number 'num1' and 'num2'.

func subtractTwoNumbers(num1: Int, num2: Int) {

}

This is the shell of our function. 'subtractTwoNumbers' is the name of our function, and it will accept two integers as its parameters.

Step 3: Writing the Function

Inside of our function, we will subtract num2 from num1. This is done with the '-' operator in Swift. We will store this result in a variable called 'result'.

func subtractTwoNumbers(num1: Int, num2: Int) {
    let result = num1 - num2
}

Step 4: Returning The Result

We've performed the operation, now we need to return the result. The 'return' keyword in Swift is used to send a value from a function. We will return the 'result' variable.

func subtractTwoNumbers(num1: Int, num2: Int) -> Int {
    let result = num1 - num2
    return result
}

Step 5: Conclusion

We have now written a function in Swift that subtracts two numbers. The function takes in two parameters, num1 and num2, subtracts num2 from num1, stores the result in the 'result' variable and then returns this value when the function is called.

Here is the full code:

func subtractTwoNumbers(num1: Int, num2: Int) -> Int {
    let result = num1 - num2
    return result
}