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: Wrong Answer)

#include <stdio.h>
#include <string.h>
int main()
{
	char s[1000];
	int l,i,d;
	gets(s);
	l=strlen(s);
	d=l/2;
		for(i=0;i<d;i++){
			if(s[i]==s[i+d])
			{continue;
			}else
			{
				break;
			}
	}
	if(i==d)
	{
		printf("Yes\n");
	}else
	{
		printf("No\n");
	}
	
	return 0;
	}