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>
#include<string.h>
int main ()
{
    char s[100];
    int a;
    scanf("%d",&a);
    scanf("%s",s);
    if (a % 2 != 0)
    {
        printf("No");
        return 0;
    }

    int i,j;
    i = 0;
    j = a/2;
    for(     ;i < a/2; i++,j++)
    {
        if (s[i] != s[j])
        { 
            printf("No");
             return 0;
        }
    }

    printf("Yes");
    
    return 0;
}