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 Ruby (2.3.3) (judge verdict: Runtime Error)

def main
  A = gets.chomp.split(' ').map(&:to_i).first
  B = gets.chomp.split(' ').map(&:to_i).first

  if (A == 1 && B == 2 )||  (A == 2 && B == 1)
    puts 3
  elsif (A==1 && B== 3) || (A == 3 && B == 1)
    puts 2
  elsif (A == 2 && B == 3) || (A == 3 && B == 2)
    puts 1
  end
end

main