Problem:
Score : 200 points

Problem Statement

Given are a positive integer N and a string S of length N consisting of lowercase English letters.

Determine whether the string is a concatenation of two copies of some string.
That is, determine whether there is a string T such that S = T + T.

Constraints

1 \leq N \leq 100

S consists of lowercase English letters.

|S| = N

Input

Input is given from Standard Input in the following format:

N
S

Output

If S is a concatenation of two copies of some string, print Yes; otherwise, print No.

Sample Input 1

6
abcabc

Sample Output 1

Yes

Let T = abc, and S = T + T.

Sample Input 2

6
abcadc

Sample Output 2

No

Sample Input 3

1
z

Sample Output 3

No

Solution in Python (3.4.3) (judge verdict: Runtime Error)

#include<iostream>
#include<string>

using namespace std;

string S;
int N;

void input(){
  cin >> N;
  cin >> S;
}

void solve(){
  input();
  string tmp = "No";
  int K = N/2;
  if(N%2==0 && S.substr(0,K)==S.substr(K,K)) tmp="Yes";
  cout << tmp <<endl;
  return;
}

int main(){
  solve();
  return 0;
}