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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <iostream>
#include <stdio.h>
using namespace std;

int main(){
    int hantei, an1, an2, n;
    char s[100], r[100], r_h[100];
    scanf("%s",s);

    for(int n_=1;s[n_] !='\0';n_++){
        n = n_;
    }
    n = n+1;
    
    for(int i=0;i<n;i++){
        r[i] = s[n-1-i];
    }

    for(int i=0;i<((n-1)/2);i++){
        r_h[i] = s[(n-1)/2-1-i];
    }
    

    hantei=0;

    for(int i=0;i<(n-1)/2;i++){
        if(s[i] != r_h[i]){hantei++;}
    }

    for(int i=0;i<n;i++){
        if(s[i] != r[i]){hantei++;}
    }

    if(hantei){
        cout << "No";
    }else{
        cout << "Yes";
    }




}