/*
Exercise: Recursive String Reversal
Coder: ttg
Date: 2/7/24

The main method is supplied; write the necessary code to get the program to work
as described.
*/

import java.util.Scanner;
public class StringReverseDriver{
    //no-touch main method
    
    public static void main(String[] args){
        public static void main(String[] args){
            String msg = "I love Computer Science!";
            System.out.println(msg);
            System.out.println();
            String rev1 = reverse(msg);
            System.out.println("rev1:\n" + rev1);
            System.out.println();
            
            msg = "Recursion is tricky!";
            String rev2 = reverseByRecursion(msg, msg.length()-1);
            System.out.println("rev2:\n" + rev2);
    }//end main method
    
    
    public static String reverse(String str){
        String temp = "";
        for(int ndx = str.length()-1; ndx >= 0; ndx--){
            String symbol = str.substring(ndx, ndx+1);
            temp += symbol;
        }
        return temp;
    }//end reverse   
    
    
    public static String reverseByRecursion(String str, int ndx){
        if(ndx < 0){
            //base case
            return "";
        }else{
            return str.substring(ndx, ndx+1) + reverseByRecursion(str, ndx-1);
        }
    }//end method reverseByRecursion
    
}//end class StringReverseDriver