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: Runtime Error)

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
int main(){
  string str;
  int l;
    cin >> str;
    l = (str.size()-1)/2;
    for(int i=0; i<(l)/2; i++){
      if(str[i] != str[l-(i+1)]){
        //cout << str[i] << ' ' << str[l-(i+1)] << endl;
        cout << "No" << endl;
        exit(1);
      }
    }
    l = (str.size()+3)/2;
    for(int i=l; i<(str.size()-l)/2; i++){
      if(str[i] != str[l -(i+1)]){
        //cout << str[i] << ' ' << str[l-(i+1)] << endl;
        cout << "No" << endl;
        exit(1);
      }
    }


    cout << "Yes" << endl;
}