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: Runtime Error)

import java.io.*;
import java.util.*;


public class Main {
    public static boolean checkPalindrom(String S){
        boolean isPalindrome=true;
        for (int i=0,j=S.length()-1;i<S.length();i++,j--){
            if (S.charAt(i)!=S.charAt(j)){
                isPalindrome=false;
                break;
            }
        }
        return isPalindrome;
    }
    public static void main (String[]args)throws IOException {
        Scanner scanner = new Scanner(System.in);
        String S = scanner.next();
        int N = S.length();
        boolean isPalindrome1=true;
        boolean isPalindrome2=true;
        boolean isPalindrome3=true;
        isPalindrome1=checkPalindrom(S);
        isPalindrome2=checkPalindrom(S.substring(0,(N-1)/2));
        isPalindrome3=checkPalindrom(S.substring(((N+3)/2),N-1));
        System.out.println(isPalindrome1&&isPalindrome2&&isPalindrome3? "Yes":"No");
    }
}