Problem:
Score : 100 points

Problem Statement

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.

Sample Input 1

4 12

Sample Output 1

16

As 4 is a divisor of 12, 4 + 12 = 16 should be printed.

Sample Input 2

8 20

Sample Output 2

12

Sample Input 3

1 1

Sample Output 3

2

1 is a divisor of 1.

Solution in C (GCC 5.4.1) (judge verdict: Accepted)

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(void){
    //%d 整数　%f 浮動小数　s% 文字列 %c もじ
    // atoi(): s->i 
    // atof(): i->s include <stdlib>
    // scanf():入力
    //strlen():文字列の長さを返す include <string.h>
    int a, b;
    scanf("%d",&a);
    scanf("%d",&b);
    printf("%d\n", b%a==0 ? a+b:b-a );

    return 0;
}