using System;

namespace Test
{
    public class HttpException : Exception
    {
        public HttpException(int status)
        {
            StatusCode = status;
        }

        public int StatusCode { get; set; }
    }

    class Program
    {
        static void TestCatch(int status)
        {
            try
            {
                throw new HttpException(status);
            }
            catch (HttpException ex) when (ex.StatusCode == 404)
            {
                Console.WriteLine("Not Found!");
            }
            catch (HttpException ex) when (ex.StatusCode >= 500 && ex.StatusCode < 600)
            {
                Console.WriteLine("Server Error");
            }
            catch (HttpException ex)
            {
                Console.WriteLine("HTTP Error {0}", ex.StatusCode);
            } 
        }
        static void Main(string[] args)
        {
            TestCatch(404);
            TestCatch(501);
            TestCatch(101);
        }
    }
}