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 (Clang 3.8.0) (judge verdict: Wrong Answer)

#include<stdio.h>
#include <iostream>
#include<string>
#include<vector>

using namespace std;
int main() {
	string str;
	bool che = false;

	cin >> str;

	for (int i = 0; i < str.length()/2; i++) {
		if (str.at(i) == str.at(str.length() - i-1)) {
			
		}
		else {
			che = true;
		}
	}
	if (str.length() < 6) {
		che = true;
	}
	for (int i = 0; i < (str.length() - 1) / 4; i++) {
		if (str.at(i) == str.at(str.length() - 3-i)) {
		}
		else {
			che = true;
		}
	}


	if (che == true) {
		cout<<"No";
	}
	else
	{
		cout << "Yes";
	}

	return 0;
}