#D6096. B +/- A
B +/- A
B +/- A
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
inputFormat
input are integers.
- 1 \leq A \leq B \leq 20
Input
Input is given from Standard Input in the following format:
A B
outputFormat
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
样例
4 1216