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.

Input

Input is given from Standard Input in the following format:
A
B

Output

Print the correct choice.

Constraints

• Each of the numbers A and B is 1, 2, or 3.
• A and B are different.

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

见题面 Input 部分

见题面 Output 部分