import java.lang.*;

import java.io.*;

import java.util.*;

class ReverseString {

public static void main(String[] args)

{

String str = "Hacktoberfast2021";

System.out.println(reverseStr(str));

}

public static String reverseStr(String input) {

byte[] byteArray = input.getBytes();

byte[] byteResult = new byte[byteArray.length];

for (int i = 0; i < byteArray.length; i++)

byteResult[i] = byteArray[byteArray.length - i - 1];

return new String(byteResult);

}

}