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)

line = readlines
len = line.length
i = 0

while i < len
    line[i] = line[i].chomp.split(' ')
    i += 1
end

p line
words = line[1]
newWord = ""

w1 = words[0]
strW1 = w1.split(//)
w2 = words[1]
strW2 = w2.split(//)

p w1
p w2
p strW1
p strW2

i = 0
strW1.each do |word| 
  newWord += strW1[i]
  newWord += strW2[i]
  i += 1
end

p newWord