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: Accepted)

import java.util.*;
public class Main {
    public static boolean isPalindrome(String s){
        char[] sc = s.toCharArray();
        for(int i=0;i<sc.length/2;i++){
            if(sc[i] != sc[sc.length-1-i]){
                return false;
            }
        }
        return true;
    }

    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String S=sc.next();
        int N = S.length();
        if(isPalindrome(S) &
                isPalindrome(S.substring(0, (N-1)/2)) &
                isPalindrome(S.substring((N+3)/2-1, N))){
            System.out.println("Yes");
        }else{
            System.out.println("No");
        }
    }
}