using System;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    public enum FlavourType

    {

        Track=0,

        Artist,

        Genre

    }

    public class Flavour

    {

        public string ID;

        public FlavourType Type;

    }

    public static void Main()

    {

        var asd = new List<Flavour>();

        for(int i = 0; i < 10; i++)

        {

            asd.Add(new Flavour{ID=i.ToString(), Type=(FlavourType)(i%3)});

        }

        foreach(var asdw in asd)

        {

            Console.WriteLine(asdw.ID);

        }

        var qwe = asd.GroupBy(flavour => flavour.Type).ToList();

        foreach(var asde in qwe)

        {

            foreach(var hurr in asde)

            {

                Console.WriteLine(hurr.ID+" "+hurr.Type);

            }

        }

    }

}