core2 #2

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

namespace ConsoleApplication4
{
    class Program
    {
        static void Main(string[] args)
        {
            var freights = new List<FreightModel>();

            if (File.Exists("tavok.txt"))
            {
                using (var sr = new StreamReader("tavok.txt"))
                {
                    while (!sr.EndOfStream)
                    {
                        var line = sr.ReadLine();

                        if (string.IsNullOrWhiteSpace(line))
                        {
                            throw new Exception("Empty line");
                        }

                        var parts = line.Split(' ');

                        freights.Add(new FreightModel
                        {
                            Day = int.Parse(parts[0]),
                            Freight = int.Parse(parts[1]),
                            Distance = int.Parse(parts[2])
                        });
                    }
                }
            }

            freights = freights.GroupBy(g => g.Day).OrderBy(g => g.Key).SelectMany(g => g.OrderBy(x => x.Freight)).ToList();

            //foreach (var item in freights)
            //{
            //    Console.WriteLine("{0} {1} {2}", item.Day, item.Freight, item.Distance);
            //}

            var first = freights.FirstOrDefault();

            if (first != null)
            {
                Console.WriteLine("First freight: {0} {1} {2}", first.Day, first.Freight, first.Distance);
            }

            var last = freights.LastOrDefault(x => x.Day == 7);

            if (last != null)
            {
                Console.WriteLine("Last freight at day 7: {0} {1} {2}", last.Day, last.Freight, last.Distance);
            }

            Console.ReadLine();
        }
    }

    class FreightModel
    {
        public int Day { get; set; }
        public int Freight { get; set; }
        public int Distance { get; set; }
    }
}