import java.util.ArrayList;

public class Main {
    public static void main(String[] args) {


//        System.out.println(addTotals(2.5, 2.5));
//        System.out.println(addTotals(5, 5));

        // Modulus Example
//        int a = 864;

//        int b = 183;
//        System.out.println("GCD of a and b is " + calcGcd(a, b));

        // Iterative factorial
        //System.out.println(factorialIterative(3));
        // reverse string
        //String name = "Frank";
        //System.out.println(reverseStringRecursive(name));
        // Towers of Hanoi
        //int disks = 4;
        //solvePuzzle(disks, "Peg 1", "Peg 2", "Peg 3");
    }

    private static int addTotals(int x, int y) {
        return x + y;
    }

    private static double addTotals(double x, double y) {
        return x + y;
    }

    private static String reverseStringRecursive(String str) {
        if (str.isEmpty()) {
            return "";
        } else {
            return (reverseStringRecursive(str.substring(1)) + str.charAt(0));
        }
    }

    static void solvePuzzle(int n, String begin, String temp, String end) {
        if (n == 1) {
            System.out.println(begin + " ---> " + end);
        } else {
            solvePuzzle(n - 1, begin, end, temp);
            System.out.println(begin + " ---> " + end);
            solvePuzzle(n - 1, temp, begin, end);
        }
    }

    public static long calcGcd(int a, int b) {
        if(b != 0) {
            System.out.println(a + " " + b + " = " + a % b);
            return calcGcd(b, a % b);
        } else {
            return a;
        }
    }

    static int printFibonacci(int n) {
        if (n == 0) {
            return 0;
        }

        if (n == 1 || n == 2) {
            return 1;
        }

        return printFibonacci(n - 2) + printFibonacci(n - 1);
    }

    private static long factorialIterative (int num) {
        int theFactorial = 1;
        for (int i = 1; i <= num; i++) {
            theFactorial *= i;
        }
        return theFactorial;
    }
}