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# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Text;
using System.Collections.Generic;
using static System.Math;
using System.Linq;

class Program
    {
static void Main(string[] args)
        {
            var HWK = Console.ReadLine().Split(' ').Select(x => long.Parse(x)).ToArray();
            var A = HWK[0];
            var B = HWK[1];
            
            if(B%A ==0 ){
              Console.WriteLine(A+B);
            }else{
              Console.WriteLine(B-A);
            }
            
        }
}