//zad1
            //a
            var elements = from car in myCars
                           where car.Model == "A6"
                           select new
                           {
                               engineType = car.Motor.Model == "TDI" ? "diesel" : "petrol",
                               avgHppl = car.Motor.HorsePower / car.Motor.Displacement
                           }
                           into p
                           group p by p.engineType into q
                           select new
                           {
                               q.First().engineType,
                               avgHPPL = q.Average(r => r.avgHppl)
                           }
                           into s
                           orderby s.avgHPPL descending
                           select s;

            Console.WriteLine("Zadanie 1a:");
            foreach (var e in elements)
            {
                Console.WriteLine(e.engineType + ": " + e.avgHPPL);
            }


            //b
            var elements2 = myCars
                .Where(x => x.Model == "A6")
                .Select(x => new
                {
                    engineType = x.Motor.Model == "TDI" ? "diesel" : "petrol",
                    avgHppl = x.Motor.HorsePower / x.Motor.Displacement
                })
                .GroupBy(x => x.engineType)
                .Select(x => new
                {
                    x.First().engineType,
                    avgHPPL = x.Average(y => y.avgHppl)
                })
                .OrderByDescending(z => z.avgHPPL);

            Console.WriteLine("Zadanie 1b:");
            foreach (var e in elements2)
            {
                Console.WriteLine(e.engineType + ": " + e.avgHPPL);
            }

            //zad 2

            Func<Car, Car, int> arg1 = delegate (Car c1, Car c2)
            {
                return c1.Motor.HorsePower < c2.Motor.HorsePower ? 1 : -1;
            };

            Predicate<Car> arg2 = delegate (Car c)
            {
                return c.Motor.Model.Equals("TDI");
            };

            Action<Car> arg3 = delegate (Car c)
            {
                string content = "Model: " + c.Model + "\nSilnik: " + c.Motor.Displacement.ToString("0.0") + " "
                        + c.Motor.Model + " Moc: " + c.Motor.HorsePower + "\nRok: " + c.Year;
                MessageBox.Show(content, "Zawartosc obiektu");
            };

            myCars.Sort(new Comparison<Car>(arg1));
            PrintCollection(myCars);

            myCars.FindAll(arg2).ForEach(arg3);
        }

        private static void PrintCollection(List<Car> cars)
        {
            foreach (var car in cars)
            {
                string empty = String.Empty;
                for (int i = 0; i < car.Model.Length % 4; ++i)
                    empty += ' ';
                Console.WriteLine("Model: {0}{1}, Moc silnika: {2}, Rok: {3}", empty, car.Model, car.Motor.HorsePower, car.Year);
            }
        }