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 9.2.1) (judge verdict: Accepted)

#include<stdio.h>
#include<string.h>


int main()
{
    char S[105];
    int N,i,j,k=1,l;
    scanf("%d",&N);
    scanf("%s",S);

    if(N%2==1)
        printf("No\n");
    else
    {
        for(i=0;i<N/2;i++)
        {
            if(S[i]==S[N/2+i])
                k=1;
            else
            {
                k=0;
                break;
            }
        }
    
    if(k==1)
        printf("Yes\n");
    else
        printf("No\n");}
    return 0;
}