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