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 C (Clang 10.0.0) (judge verdict: Wrong Answer)

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

int main(){
	
	int n;
	scanf ("%d", &n);
	getchar();
	char str[n];
	scanf ("%[^\n]", str);
	int check = 0;
	int mid = n / 2;
	
	for (int i = 0, j = mid; i < mid,j < n; i++, j++){
			if (str[i] != str[j]){
				check = 1;
			}
			else{
				check = 0;
			}
		}
	
	if (check == 1 || n <= 1){
		printf ("No\n");
	}
	else{
		printf ("Yes\n");
	}
	
	return 0;
}