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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.io.InputStream;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;

class Main {
    public static void main(String args[]) {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        try{
            int n = Integer.parseInt(br.readLine());
            char[] s = br.readLine().toCharArray(), t = br.readLine().toCharArray();
            for(int i = 0; i <= n; ++i){
                boolean ok = true;
                for(int j = 0; j < n - i; ++j){
                    if(s[i + j] != t[j]){
                        ok = false;
                        break;
                    }
                }
                if(ok){
                    System.out.println(n + i);
                    return;
                }
            }
        }catch(IOException e){
            e.printStackTrace();
        }
    }
}