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(){
    char s[101];
    int palin,i,flag=0;
    scanf("%s",s);

    int n=strlen(s);

    for(i=0;i < ((n -1)/2)-1 ;++i){
        if(s[i]!=s[((n-1)/2)-1 - i]){ //comparando o primeiro com o ultimmo
        flag =1;
        break;
    }

    for(int i=(n+ 3)/2; i<n -1; ++i){
        if(s[i]!=s[n -1 -i]){
            flag =1;
            break;
        }
    }
}
    if(flag){
        printf("No\n");

    }else {
        printf("Yes\n");
    }





    return 0;
}