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.