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;

using LL = long long;
using LD = long double;
 
LL mod = 998244353;

int main()
{
	string s;
	cin >> s;
	LL n = s.size();
	LL q = 1, w = 1;

	string t = "";
	for (LL i = 0; i < n/2; ++i) {
		if (s[i] != s[n-1-i]) {
			q = 0;
		}
		t.push_back(s[i]);
	}


	for (LL i = 0; i < t.size()/2; ++i) {
		if (t[i] != t[t.size()-1-i]) {
			w = 0; break;
		}
	}
	
	if (q&&w) {
		cout << "Yes\n";
	}
	else {
		cout << "No\n";
	}


}