public void Test() { Battery bat = new Battery("1sd34", 500, 100, BatteryType.NiCd); Display disp = new Display(); GSM phone = new GSM("6", "IPhone", bat.ToString(), disp.ToString()); phone.AddCall("12.12.2012", "15:00", "+359 885 635338", 500); phone.AddCall("04.04.2004", "12:00", "+359 885 643453", 200); phone.AddCall("01.03.2014", "09:00", "+359 884 654634", 100); foreach (var item in GSM.CallList) { Console.WriteLine(item); } Console.WriteLine("Total price of all calls in history: " + phone.CalculateCallPrice(0.37) + "BGN"); Console.WriteLine("========================="); phone.DeleteCall(); foreach (var item in GSM.CallList) { Console.WriteLine(item); } Console.WriteLine("Total price of all calls in history: " + phone.CalculateCallPrice(0.37) + "BGN"); Console.WriteLine("========================="); phone.ClearHistory(); foreach (var item in GSM.CallList) { Console.WriteLine(item); } }