Program to find out shortest palindrome of given string

package shortestpalindromeexample.java;

import java.util.Scanner;

public class ShortestPalindromeDemo {

public static String shortestPalindrome(String str) {

     

int x=0;  

int y=str.length()-1;

     

  while(y>=0){

     if(str.charAt(x)==str.charAt(y)){

          x++;

         }

            y--;

  }

if(x==str.length())

return str;

String suffix = str.substring(x);

String prefix = new StringBuilder(suffix).reverse().toString();

String mid = shortestPalindrome(str.substring(0, x));

return prefix+mid+suffix;

}

public static void main(String[] args) {

Scanner in = new Scanner(System.in);

System.out.println("Enter a String to find out shortest palindrome");

String str=in.nextLine();

System.out.println("Shortest palindrome of "+str+" is "+shortestPalindrome(str));

}

}

Output:

Enter a String to find out shortest palindrome

java

Shortest palindrome of java is avajava