You are given two integers A and B. Find the largest value among A+B, A-B and $A \times B$.

Constraints

• -$1000 \leq A,B \leq 1000$
• All values in input are integers.

Input

Input is given from Standard Input in the following format:

A B

Output

Print the largest value among A+B, A-B and $A \times B$.

Examples

Input

3 1

Output

4

Input

4 -2

Output

6

Input

0 0

Output

0

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