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],S_cp[100];
  char S_1[50],S_1cp[50],S_2[50],S_2cp[50];
  int i,N,ans1,ans2,ans3;
  
  scanf("%s",&S);
  N = strlen(S);
  
  for(i=0;i<N;i++){
    S_cp[i] = S[N-1-i];
  }
  
  for(i=0;i<=N/2;i++){
    S_1[i] = S[i];
    S_1cp[i] = S[N/2-i];
  }
  
  for(i=0;i<=N/2;i++){
    S_2[i] = S[(N+2)/2+i];
    S_2cp[i] = S[N-i];
  }
  
  ans1 = strcmp(S,S_cp);
  ans2 = strcmp(S_1,S_1cp);
  ans3 = strcmp(S_2,S_2cp);
  
  if(ans1==0){
    if(ans2==0){
      if(ans3==0){
        printf("Yes\n");
      }else{
        printf("No\n");
      }
    }else{
      printf("No\n");
    }
  }else{
    printf("No\n");
  }
  
  
  return 0;
}