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 Java (OpenJDK 11.0.6) (judge verdict: Wrong Answer)

            import java.util.Scanner;
             
            public class Main{
              public static void main(String[] args){
             
                Scanner scan = new Scanner(System.in);
             
                String word = scan.nextLine();
                int length = word.length();
             
                if (isPalindrome(word) && isPalindrome(word.substring(0, (length-1)/2)) && isPalindrome(word.substring(((length+3)/2)-1, length))){
                  System.out.println("Yes");
                }
                else {
                  System.out.println("No");
                }
              }
             
              public static boolean isPalindrome(String string){
                for(int i = 0; i < string.length()/2; i++){
                  if (string.substring(i).compareTo(string.substring(string.length()-1-i)) == 0){
                    return false;
                  }
                }
                return true;
              }
            }