#pragma warning disable

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.Serialization.Formatters.Binary;
using System.Text;
using System.Text.RegularExpressions;
using System.Diagnostics;
using System.Numerics;
using System.Collections;

static class MainClass
{
    public static void Main(string[] args)
    {
        //var nm = Console.ReadLine().SplittedStringToInt32List();
        //var n = nm[0];
        //var m = nm[1];
        //var kms = new bool[m];
        //var kmlsit = new bool[n,m];


        //for (int i = 0; i < n; i++)
        //{
        //    var count = 0;
        //    var km = Console.ReadLine().SplittedStringToInt32List();
        //    foreach (var item in km)
        //    {
        //        kmlsit[i, item - 1] = true;
        //    }
        //}
        //var counts = 0;
        //for (int i = 0; i < m; i++)
        //{
        //    var isok = true;
        //    for (int j = 0; j < n; j++)
        //    {
        //        isok = kmlsit[j, i] && isok;
        //    }
        //    if (isok)
        //        counts++;
        //}
        //Console.WriteLine(counts);

        //Console.ReadLine();
        var ab = Console.ReadLine().SplittedStringToInt32List();
            
        if (ab[1] % ab[0] == 0)
        {
            Console.WriteLine(ab[1] + ab[0]);
        }
        else
        {
            Console.WriteLine(ab[1] - ab[0]);
        }

    }


    public static int Gcd(int a, int b)
    {
        if (b == 0)
            return a;
        return Gcd(b, a % b);
    }
    public static BigInteger Gcd(BigInteger a, BigInteger b)
    {
        if (b == 0)
            return a;
        return Gcd(b, a % b);
    }

    public static long f(long n,long b)
    {
        if (n < b)
        {
            return n;
        }
        else
        {
            return f((long)Math.Floor((double)n/b),b) + n % b;
        }
    }

    public static string N(long n,long b)
    {
        var sb = new StringBuilder();
        while (true)
        {
            sb.Append((n % b).ToString());
            n /= b;
            if (n < b)
            {
                sb.Append(n.ToString());
                break;
            }
        }
        return new string( sb.ToString().Reverse().ToArray() );
    }

    #region ライブラリ
    public static long ToInt64(this string str) => long.Parse(str);
    public static int ToInt32(this string str) => int.Parse(str);
    public static BigInteger ToBigInteger(this string str) => BigInteger.Parse(str);
    public static List<string> SplittedStringToList(this string str) => str.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).ToList();
    public static List<int> SplittedStringToInt32List(this string str) => str.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).Select(x => int.Parse(x)).ToList();
    public static List<long> SplittedStringToInt64List(this string str) => str.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).Select(x => long.Parse(x)).ToList();
    public static List<BigInteger> SplittedStringToBigInteger(this string str) => str.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).Select(x => BigInteger.Parse(x)).ToList();
    public const int INF = int.MaxValue / 2;
    public const long LONGINF = long.MaxValue / 2;
    public const int Mod1e9 = 1000000007;
    

    public static void PrintArray(bool[,] array)
    {
        for (int i = 0; i < array.GetLength(0); i++)
        {
            var sb = new StringBuilder();
            for (int j = 0; j < array.GetLength(1); j++)
            {
                sb.Append(array[i, j]).Append(" ");
            }
            Console.WriteLine(sb.ToString());
        }
    }

    #endregion
}



Measured memory_bytes: 13268