using System;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    public partial class Sdsl

    {

        public int Id { get; set; }

        public int RegUserId { get; set; }

        public bool? SdslConfirmed { get; set; }

        public string SdslReason { get; set; }

        public bool IsActive { get; set; }

        public DateTime DateModified { get; set; }

        public DateTime DateClosed { get; set; }

        public Guid? ChangedByUser { get; set; }

    }

    public static void Main()

    {

        var sdsl = new HashSet<Sdsl>();

        sdsl.Add(null);

        var s = sdsl.OrderByDescending(x => x.Id).FirstOrDefault();

        Console.WriteLine("Hello World");

    }

}