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: Wrong Answer)

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

int main(void)
{
   char s[100],c[100],a;
   int n,i,b,j;

   scanf("%s",s);
   strcpy(c,s);
   n=strlen(s);
   if((n%2)!=(1)){printf("No\n"); return 0;}
   for(i=0,j=n-1; i<n/2; i++,j--){
      a=c[i];
      c[i]=c[j];
      c[j]=a;
   }
   b=strcmp(s,c);
   if(b!=0){ printf("No\n"); return 0;}
   else{printf("Yes\n"); return 0;}
}