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++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>

int main(){
    int n;
    scanf("%d", &n);
    char s[n];
    for(int i = 0; i < n; i++) scanf("%c", &s[i]);
    int counter = 0;
    if(n%2 == 0){
        for(int i = 0; i< n/2; i++) {
            if(s[i] == s[n/2+i]) counter++; 
        }
    }
    if(n==1) printf("No");
    else{
        if(counter == n/2) printf("Yes");
        else printf("No");
    }
    return 0;
}