Swift Navigation Application

FizzBuzz.swift

// Written.... In Swift
import Foundation

///  Generates the first n Fibonacci numbers printing
///  "Buzz" when F(n) is divisible by 3.
///  "Fizz" when F(n) is divisible by 5.
///  "FizzBuzz" when F(n) is divisible by 15.
///  "BuzzFizz" when F(n) is prime.
///  the value F(n) otherwise.
///
/// - Parameter n: number of Fibonacci numbers to print
func FizzBuzz(n: Int) {
    
    // If n < 2 only print "seed" values
    let x = (n >= 1) ? 1 : 0;
    
    // print up to and including x (Maximum 1)
    for num in 0...x {
        print(num)
    }
    
    // Continue Sequence only for numbers above 1
    guard (n > 1) else {
        return
    }
    
    // Storage for previous numbers in sequence
    var prevValues = [ 0 , 1]
    
    for num in 2...n {
        var newValue = prevValues[0] + prevValues[1]
        var specialCase = false
        
        if (isPrime(num: newValue)) {
            print("BuzzFizz", terminator: "")
            specialCase = true
        } else {
            // Divisible by 5
            if (newValue % 5 == 0) {
                print("Fizz", terminator: "")
                specialCase = true
            }
            
            // Divisible by 3
            if (newValue % 3 == 0) {
                print("Buzz", terminator: "")
                specialCase = true
            }
            
            // Print number
            if (!specialCase) {
                print(newValue, terminator: "")
            }
        }
        // Add new line
        print("")
        
        prevValues[0] = prevValues[1]
        prevValues[1] = newValue
    }
}

/// Checks if input is a prime number
///
/// - Returns: true for prime number input
func isPrime(num: Int) -> Bool {
    guard num > 1 else {
        return false
    }
    
    var i = 2
    // Only need to check up to square root of input
    // C style for loops deprecated in Swift, must use while
    while (i*i <= num) {
        // Not a prime if has factor
        if (num % i == 0) {
            return false
        }
        i += 1
    }
    return true
}