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 5.4.1) (judge verdict: Accepted)

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include <math.h>

int main() {

    int n;
    char s[100];

    scanf("%d %s", &n, s);

    int isCheck = 1;

    if (n % 2 != 0) {
        isCheck = 0;
    } else {

        int num = n / 2;

        for (int i = 0; i < num; i++) {

            if (s[i] != s[i + num]) {

                isCheck = 0;
                break;
            }

        }

    }
    
    printf("%s",(isCheck==1 ? "Yes" : "No"));


    return 0;

}