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 C (GCC 5.4.1) (judge verdict: Accepted)

#include <stdio.h>
#include <string.h>

int checkPalindrome(char* str, int beg, int end){
	int i;
	for(i=0;i<(end-beg+1)/2;i++){
		if(str[beg+i]!=str[end-i])
			return 0;
	}
	return 1;
}

int main(void) {
	// your code goes here
	char str[100];
	scanf("%s",str);
	int n = strlen(str);
	int ctr = (n - 1)/2;
	int strong = 0;
	if(checkPalindrome(str,0,n-1)==1){
		if(checkPalindrome(str,0,ctr-1)==1){
			if(checkPalindrome(str,ctr+1,n-1)==1)
				strong = 1;
		}
	}
	
	if(strong==1)
		printf("Yes\n");
	else
		printf("No\n");
	
	
	
	return 0;
}