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 (Clang 3.8.0) (judge verdict: Accepted)

#include <stdio.h>
#include <string.h>
int main(void){
  char input[110];
  int i,j;
  int miss=0;
  gets(input);
  i=0;
  j=strlen(input)-1;
  while(i!=j){
      if(input[i]!=input[j]){
          miss++;
      }
      i++;
      j--;
  }
  if(miss==0){
      i=0;
      j=((strlen(input)+3)/2)-1;
      while(i!=((strlen(input)-1)/2)){
          if(input[i]!=input[j]){
              miss++;
          }
          i++;
          j++;
      }
      
  }
  if(miss!=0){
      printf("No\n");
  }else{
      printf("Yes\n");
  }
  return 0;
}