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: Wrong Answer)

#include <bits/stdc++.h>
using namespace std;
#define ll long long int
bool check(string &str)
{
    ll l = str.size();
    ll i,j;
    for(i = 0; i<l; i++)
    {
        if(str[i] != str[l-i-1])
        {
            return false;
            break;
        }
    }
    return true;
}
int main()
{
    string str;
    getline(cin,str);
    ll l = str.size();
    ll i,j;
    ll n = (l - 1)/2;
    ll k = (l+3)/2;
    string a = "",b="";
    for(i = 0; i<n; i++)
        a+= str[i];
    for(i = k-1; i<l; i++)
        b+= str[i];
    if(l % 2 != 0)
    {
        if(check(a) == true && check(b) == true)
            cout << "Yes" << endl;
        else
            cout << "No" << endl;
    }
    else
        cout << "No" << endl;

    return 0;
}