Problem:
Score : 200 points

Problem Statement

A string S of an odd length is said to be a strong palindrome if and only if all of the following conditions are satisfied:

S is a palindrome.

Let N be the length of S. The string formed by the 1-st through ((N-1)/2)-th characters of S is a palindrome.

The string consisting of the (N+3)/2-st through N-th characters of S is a palindrome.

Determine whether S is a strong palindrome.

Constraints

S consists of lowercase English letters.

The length of S is an odd number between 3 and 99 (inclusive).

Input

Input is given from Standard Input in the following format:

S

Output

If S is a strong palindrome, print Yes;
otherwise, print No.

Sample Input 1

akasaka

Sample Output 1

Yes

S is akasaka.

The string formed by the 1-st through the 3-rd characters is aka.

The string formed by the 5-th through the 7-th characters is aka.
All of these are palindromes, so S is a strong palindrome.

Sample Input 2

level

Sample Output 2

No

Sample Input 3

atcoder

Sample Output 3

No

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)


import java.util.Scanner;
public class Main { 
    public static void main(String args[])
   {
       int j;
      String str, rev ="" , rev1="", rev2= "";
      Scanner sc = new Scanner(System.in);
 
      str = sc.nextLine();
 
      int length = str.length();
      
      int n1 = (length-1)/2;
      int n2 = (length+3)/2;
      
      String st = "";
      String st1 = "";
      st = str.substring(0,n1);
      st1 = str.substring(n2-1,length);
        
    for ( j = n1 - 1; j >= 0; j-- ){
         rev1 = rev1 + st.charAt(j);
         rev2 = rev2 + st1.charAt(j);
    }
      for ( int i = length - 1; i >= 0; i-- )
         rev = rev + str.charAt(i);
 
      if (str.equals(rev) && st.equals(rev1) && st1.equals(rev2))
         System.out.println("YES");
      else
         System.out.println("No");
     
   }
}