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 JavaScript (node.js v5.12) (judge verdict: Accepted)

function main(arg) {
	arg = arg.trim().split('\n');
  	arg = arg.map(str => parseInt(str, 10));
  	var a = arg[0], b = arg[1];
	var num = [1, 2, 3];
	var out = num.filter(o => o !== a && o != b);
	console.log(out[0]);
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));