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 Java (OpenJDK 11.0.6) (judge verdict: Wrong Answer)

import java.util.*;
import java.io.*;

public class Main {
		public static void main(String[] args) throws IOException {
		
		// 入出力高速化 java.io.* とthrows IOExceptionを忘れずに
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		
		int N = Integer.parseInt(br.readLine());
		String S = br.readLine();
		String T = br.readLine();
		
		int Tstart = 0;
		for(int t=T.length(); t>0;t--){
			for(int s=0; s<S.length(); s++){
				if(S.substring(s).contentEquals(T.substring(0,t))){
					Tstart = t;
				}
			}
		}
		
        System.out.print(S.length()+T.length()-Tstart);
    }
}