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: Accepted)

#include<stdio.h>
#include<string.h>
int main(){
	int n;
	char a[120];
	scanf("%d",&n);
	if(n%2==1) printf("No");
	else{
	for(int i=0;i<n;i++) scanf(" %c",&a[i]);
	for(int i=0;i<n/2;i++)
		if(a[i]!=a[i+n/2]){
			printf("No");
			return 0;
		}
	printf("Yes");
}
	return 0;
}