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)

package test2;
import java.util.*;


public class Main {

	// test 2 B - String Palindrome
	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		
		String input = sc.next();
		int lenInput = input.length();
		
		String str1 = input.substring(0,(lenInput-1)/2);
		String str2 = input.substring((lenInput+1)/2, lenInput);

        StringBuffer str1b = new StringBuffer(str1);
   
        String str1r = str1b.reverse().toString();

		log( (str1.equals(str2) && str1r.equals(str2)) ? "yes" : "no"); 
		sc.close();
	}

	static void log(String s) {
		System.out.println(s);
	}
	
}