using System;

​

public enum AllowableSaleTypes

{

    None = 0,

    X = 1,

    Y = 2,

}

​

public class Program

{

    public static void Main()

    {

        var none = AllowableSaleTypes.None;

        var x = AllowableSaleTypes.X;

        var none_x = AllowableSaleTypes.None | AllowableSaleTypes.X;

        var x_y = AllowableSaleTypes.X | AllowableSaleTypes.Y;

        Console.WriteLine($"none: [{none}]");

        Console.WriteLine($"x: [{x}]");

        Console.WriteLine($">>>> none_x: [{none_x}]");

        Console.WriteLine($"x_y: [{x_y}]");

    }

}