C# enum flag comparison with bitwise operators, C#

Language: Layout:

//Rextester.Program.Main is the entry point for your code. Don't change it.
//Compiler version 4.0.30319.17929 for Microsoft (R) .NET Framework 4.5

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace Rextester
{
    public class Program
    {
        [Flags]
        public enum Choices
        {
            None    = 0,        //0,
            First   = 1 << 0,   //1
            Second  = 1 << 1,   //2
            Third   = 1 << 2,   //4
            Fourth  = 1 << 3    //8
        }
        
        public static void Main(string[] args)
        {
            
            Choices firstandsecond = Choices.First | Choices.Second;
            int asdf = (int)firstandsecond;
            Choices casted = (Choices)asdf;
            bool hasFirst = (casted & Choices.First) != 0; //same as Choices.None
            bool hasSecond = (casted & Choices.Second) != Choices.None;  //same as 0
            bool hasThird = (casted & Choices.Third) != Choices.None;
            Console.WriteLine(asdf);
            Console.WriteLine(casted);
            Console.WriteLine(hasFirst);
            Console.WriteLine(hasSecond);
            Console.WriteLine(hasThird);
            Console.WriteLine("-----");
            Choices CChoice = Choices.None;
            CChoice |= Choices.First;
            CChoice |= Choices.Second;
            Console.WriteLine(CChoice);
            CChoice |= Choices.Third;
            Console.WriteLine(CChoice);
            CChoice &= ~Choices.First;
            Console.WriteLine(CChoice);
            
        }
    }
}

Show compiler warnings [ + ] Show input
Compilation time: 0,11 sec, absolute running time: 0,09 sec, cpu time: 0,09 sec, average memory usage: 12 Mb, average nr of threads: 2