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++ (GCC 9.2.1) (judge verdict: Accepted)

#include <stdio.h>

int main() {
	int Zx, count = 0;
	int count1, count2;
	char Yz[104] = {};
	scanf("%d %s", &Zx, &Yz);
	if (Zx % 2 != 0) {
		printf("No");
		return 0;
	}
	int haafu = Zx / 2;
	for (int u = 0; u < haafu; u++) {
		if (Yz[u] == Yz[u + haafu]) {
			count++;
		}
	}
	count == haafu ? printf("Yes") : printf("No");

	return 0;
}