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 <bits/stdc++.h>
using namespace std;

int main(void) {
    string s;
    string check1;
    string check2;

    cin >> s;

    check1 = s;check2 = s;
    reverse(check2.begin(), check2.end());

//    cout << check1 << endl;
//    cout << check2 << endl;
    if(check1 != check2) goto ng;
    

    check1 = s;
    check1 = s.substr(0, s.size() / 2);
    check2 = check1;
    reverse(check2.begin(), check2.end());

    if(check1 != check2) goto ng;
//    cout << check1 << endl;
//    cout << check2 << endl;

    check1 = s.substr(s.size()/2 + 1, s.size() / 2);
    check2 = check1;
    reverse(check2.begin(), check2.end());
    if(check1 != check2) goto ng;

//    cout << check1 << endl;
//    cout << check2 << endl;

    cout << "Yes\n";
    return 0;

ng:
    cout << "No\n";
    return 0;
}