public static void Main() { try { Display display = new Display(4, 16000000); Battery battery = new Battery(620, 8, Battery.BatteryModel.NiMH); GSM phone = new GSM("One", "HTC", 850, "Person", battery, display); GSMTest test = new GSMTest(); Console.WriteLine("============="); test.GSMTesting(); Console.WriteLine("============="); DateTime time = new DateTime(); time = DateTime.Now; Calls[] call = new Calls[5]; //making some phone calls for (int i = 0; i < 5; i++) { time = time.AddDays(i); string phoneNumber = "0888999999"; int duration = i + 100; call[i] = new Calls(time, phoneNumber, duration); phone.AddCall(call[i]); } Console.WriteLine(); decimal pricePerMinute = 0.37m; //display call information phone.CallHistory(); Console.WriteLine("============="); phone.TotalPriceOfCalls(pricePerMinute); Console.WriteLine("============="); phone.FindLongestCall(); phone.TotalPriceOfCalls(pricePerMinute); Console.WriteLine("============="); phone.ClearCallHistory(); phone.CallHistory(); } catch (Exception ex) { Console.WriteLine(ex.Message); } }