Recursion in Swift with example

Recursion in Swift

Recursion in Swift involves a function calling itself to solve a problem. A recursive function typically consists of two main parts:

• Base Case: This is the condition that stops the recursion. Without a base case, a recursive function would call itself indefinitely, leading to a stack overflow.
• Recursive Step: This is where the function calls itself with a modified input, moving closer to the base case.

Example: Calculating Factorial using Recursion

func factorial(number: Int) -> Int {
    // Base case: If number is 0 or 1, return 1
    if number == 0 || number == 1 {
        return 1
    } 
    // Recursive step: Call factorial with (number - 1)
    else {
        return number * factorial(number: number - 1)
    }
}

// Example:
let num = 5
let result = factorial(number: num)
print("The factorial of \(num) is: \(result)") 

Output:
The factorial of 5 is: 120