Problem:
Score: 100 points

Problem Statement

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.

Sample Input 1

3
1

Sample Output 1

2

When we know 3 and 1 are both wrong, the correct choice is 2.

Sample Input 2

1
2

Sample Output 2

3

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Runtime Error)

package ABC148;

import java.util.Arrays;
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

public class Main {

  public static void main(String[] args) {
    // TODO 自動生成されたメソッド・スタブ
    Scanner scanner = new Scanner(System.in);
    Set<Integer> set = new HashSet<Integer>(Arrays.asList(1, 2, 3));
    int number1 = scanner.nextInt();
    int number2 = scanner.nextInt();
    set.remove(number1);
    set.remove(number2);
    for (Integer integer : set) {
      System.out.println(integer);
    }
  }

}