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 Java7 (OpenJDK 1.7.0) (judge verdict: Accepted)

import javax.net.ssl.SSLContext;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.List;

public class Main {

    public static void main(String[] args) throws IOException {

        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));

        int N = Integer.parseInt(reader.readLine());

        String s = reader.readLine();
        String t = reader.readLine();

        int len = s.length();
        for (int i = 0; i < t.length(); i++) {
            String tt = t.substring(0, t.length() - i);
            int pos = s.indexOf(tt);
            if (pos >= 0) {
                len += pos;
                if (len < N)
                    System.out.println(N);
                else
                    System.out.println(len);
                return;
            }
        }

        len += t.length();

        if (len < N)
            System.out.println(N);
        else
            System.out.println(len);

//        PrintWriter writer = new PrintWriter(System.out);
//
//        writer.close();


    }
}