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()
{
	int i,n,flag=0,count=0;
	char s[1000];
	scanf("%d",&n);
	fflush(stdin);
	if(n%2==0)
		flag=1;
	else
		flag=0;	
	for(i=1;i<=n;i++)
	scanf("%c",&s[i]);
	if(flag==0)
		printf("No\n");
	if(flag==1)
	{
	for(i=1;i<=n/2;i++)
	{
		if(s[i]==s[n/2+i])
			count++;
			else
				break;
	}	

	if(count==n/2)
		printf("Yes\n");
	else
		printf("No\n");

	}



}