using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        var exchangeRequest1 = new ExchangeRequestModel();

        exchangeRequest1.ExchangeRequestId = 1;

        exchangeRequest1.Action = "Add";

        exchangeRequest1.ExchangeAttempts =  null;

        var exchangeRequest0 = new ExchangeRequestModel();

        exchangeRequest0.ExchangeRequestId = 1;

        exchangeRequest0.Action = "Add";

        exchangeRequest0.ExchangeAttempts =  0;

        var exchangeRequest3 = new ExchangeRequestModel();

        exchangeRequest3.ExchangeRequestId = 1;

        exchangeRequest3.Action = "Add";

        exchangeRequest3.ExchangeAttempts =  1;

        var exchangeRequest2 = new ExchangeRequestModel();

        exchangeRequest2.ExchangeRequestId = 2;

        exchangeRequest2.Action = "Add";

        exchangeRequest2.ExchangeAttempts =  2;

         List<ExchangeRequestModel> ExchangeRequestList = new List<ExchangeRequestModel>();

         ExchangeRequestList.Add(exchangeRequest1);

         ExchangeRequestList.Add(exchangeRequest2);

         ExchangeRequestList.Add(exchangeRequest3);

         ExchangeRequestList.Add(exchangeRequest0);

        var exchangeAttemptsList = ExchangeRequestList.Where(x => x.ExchangeAttempts.HasValue ?  x.ExchangeAttempts.Value: 1 <= 1).ToList();

         foreach (var exchangeAttempt in exchangeAttemptsList)

         {

             Console.WriteLine(exchangeAttempt);

         }

    }

     public class ExchangeRequestModel

    {

        public int ExchangeRequestId { get; set; }

        public string Action { get; set; }

        public int? ExchangeAttempts { get; set; }

    }

}