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 n;
  char s[200];
  char s1[100];
  char s2[100];
  int a;
  
  scanf("%d",&n);
  a=n/2;
  
  if(n%2==1){
    printf("No");
  }
  
  else{
    for(int i=0;i<n;i++){
      scanf("%s",&s[i]);
    }
    //printf("%s\n",s);
    /*
    for(int k=0;k<a;k++){
    s1[k]=s[k];
    }
    printf("%s\n",s1);
    
    for(int j=a;j<n;j++){
    s2[j-a]=s[j];
    }
    printf("%s\n",s2);
    if(strcmp(s1,s2)!=0){
        printf("No");
      }
    else printf("Yes");
    */
    for(int i=0;i<a;i++){
    if(s[i]!=s[i+a]){
      printf("No");
      break;
      //break;
    }
    else {}
    }
    printf("Yes");
  }
  return 0;
}