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: Accepted)

import java.util.*;


public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);
        
        String s = sc.next();
        StringBuilder sb1 = new StringBuilder(s);
        if(!(s.equals(sb1.reverse().toString()))){
        	System.out.println("No");
            return;
        }
        
        String s2 = s.substring(0, (s.length()-1)/2);
        StringBuilder sb2 = new StringBuilder(s2);
        if(!(s2.equals(sb2.reverse().toString()))){
        	System.out.println("No");
            return;
        }
        
        String s3 = s.substring(((s.length()+3)/2)-1);
        StringBuilder sb3 = new StringBuilder(s3);
        if(!(s3.equals(sb3.reverse().toString()))){
        	System.out.println("No");
            return;
        }
        
        System.out.println("Yes");
	}
}