public class Main {
    public static void main(String[] args){
        Scanner scan = new Scanner(System.in);
        System.out.println("Please enter the name of the method you want to run.");
        String method = scan.next();
        if (method.equals("recursivePrinter")){
            System.out.println("Please enter the input for the method.");
            int num = scan.nextInt();
            recursivePrinter(num);
        }
        if (method.equals("reversePrint")){
            System.out.println("Please enter the input for the method.");
            String word = scan.next();
            reversePrint(word);
            System.out.println();
        }
        if (method.equals("factorial")){
            System.out.println("Please enter the input for the method.");
            int num  = scan.nextInt();
            System.out.println(factorial(num));
        }
    }
    public static void recursivePrinter(int levels){
        if (levels > 0){
            System.out.println("Going down! " + levels);
            recursivePrinter(levels-1);
        }
        if (levels != 0) {
            System.out.println("Coming back up! " + levels);
        }
    }
    public static void reversePrint(String str){
        if (str.length() >= 1) {
            System.out.print(str.substring(str.length()-1,str.length()));
            reversePrint(str.substring(0,str.length()-1));
        }
    }
    public static int factorial(int num){
        int result;
        if(num<=1) {
            return 1;
        }
        else {
            result = factorial(num - 1) * num;
            return result;
        }
    }
}