You are given positive integers A and B.

If A is a divisor of B, print A + B; otherwise, print B - A.

Constraints

• All values in input are integers.
• $1 \leq A \leq B \leq 20$

Input

Input is given from Standard Input in the following format:

A B

Output

If A is a divisor of B, print A + B; otherwise, print B - A.

Examples

Input

4 12

Output

16

Input

8 20

Output

12

Input

1 1

Output

2

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