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.Collections.Generic;
using System.Linq;

class Program
{
	static void Main()
	{
		var AB = Array.ConvertAll(Console.ReadLine().Split(new[] { ' ' }), number => int.Parse(number));

		if (AB[1] % AB[0] == 0) {
			Console.WriteLine(AB.Sum());
		} else {
			Console.WriteLine(AB[1] - AB[0]);
		}

		//デバッグ実行での確認用。そのまま提出しても問題なし
		Console.ReadKey();
	}
}