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 PHP (5.6.30) (judge verdict: Accepted)

<?php 
fscanf(STDIN, "%d", $a);
fscanf(STDIN, "%d", $b);

if($a+$b == 3){
  echo "3";
}elseif ($a+$b == 4) {
  echo "2";
}elseif ($a+$b == 5) {
  echo "1";
}

 ?>