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;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;

namespace kyoupuro
{
    class MainClass
    {
        public static void Main()
        {
            MainClass mainClass = new MainClass();
            //var myarray = mainClass.IntInit();
            var myarray = new List<int>(Console.ReadLine().Split(' ').Select(int.Parse));
            mainClass.Start(myarray);
        }

        List<List<String>> Init() {
            int maxindex = int.Parse(Console.ReadLine());

            List<List<String>> array = new List<List<String>>();

            for (int i = 0; i < maxindex; i++)
                array.Add(new List<String>(Console.ReadLine().Split(' ')));

            return array;
        }

        List<List<int>> IntInit() {
            int maxindex = int.Parse(Console.ReadLine());

            List<List<int>> array = new List<List<int>>();

            for (int i = 0; i < maxindex; i++) {
                array.Add(new List<int>(
                    Console.ReadLine().Split(' ').Select(int.Parse)));
            }

            return array;
        }

        void Start(List<int> e) {
            if (e[1] % e[0] == 0) Console.WriteLine(e[1] + e[0]);
            else Console.WriteLine(e[1] - e[0]);

        }
    }
}