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;
using System.Text;
using System.Threading.Tasks;

namespace AtCoder118A
{
    class Program
    {
        static void Main(string[] args)
        {
            // 整数の入力
            //int a = int.Parse(Console.ReadLine());
            // スペース区切りの整数の入力
            string[] input = Console.ReadLine().Split(' ');
            int A = int.Parse(input[0]);
            int B = int.Parse(input[1]);
            // 文字列の入力
            //string s = Console.ReadLine();
            int c = (B % A);
            if (c == 0)
            {
                Console.WriteLine(A+B);
            }
            else
            {
                Console.WriteLine(B-A);
            }
        }
    }
}