Problem:
Score : 200 points

Problem Statement

Snuke is interested in strings that satisfy the following conditions:

The length of the string is at least N.

The first N characters equal to the string s.

The last N characters equal to the string t.

Find the length of the shortest string that satisfies the conditions.

Constraints

1≤N≤100

The lengths of s and t are both N.

s and t consist of lowercase English letters.

Input

The input is given from Standard Input in the following format:

N
s
t

Output

Print the length of the shortest string that satisfies the conditions.

Sample Input 1

3
abc
cde

Sample Output 1

5

The shortest string is abcde.

Sample Input 2

1
a
z

Sample Output 2

2

The shortest string is az.

Sample Input 3

4
expr
expr

Sample Output 3

4

The shortest string is expr.

Solution in C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>

int main(){
  char s[100] = {};
  char t[100] = {};
  int n = 0;
  int i = 0;
  int j = 0;
  int hoge = -1;
  int flag = 0;
  
  scanf("%d",&n);
  scanf("%s",s);
  scanf("%s",t);
  for(i=0;i<=n;i++){
    flag = 1;
    for(j=0;j<i;j++){
      if(s[j+i] == t[j]){
        flag = 1;
      }else{
      	flag = 0;
        break;
      }
    }
    if(flag){
      hoge = i;
    }
  }
  
  if(hoge != -1){
    printf("%d",(n-hoge)+2*(hoge));
  }else{
    printf("%d",2*n);
  }
  return 0;
}