Takahashi is solving quizzes. He has easily solved all but the last one.

The last quiz has three choices: 1, 2, and 3.

With his supernatural power, Takahashi has found out that the choices A and B are both wrong.

Print the correct choice for this problem.

Constraints

* Each of the numbers A and B is 1, 2, or 3.
* A and B are different.

Input

Input is given from Standard Input in the following format:


A
B


Output

Print the correct choice.

Examples

Input

3
1


Output

2


Input

1
2


Output

3

import java.util.Scanner;
public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		int a = sc.nextInt();
		int b = sc.nextInt();
		
		int ans = 0;
		
		for(int i = 1 ;i <= 3 ;i++) {
			if(i % 3 == a % 3 || i % 3 == b % 3) {
				continue;
			}
			else {
				ans = i;
				break;
			}
		}
		System.out.println(ans);
		
		
	}
}
