public static void CallHistoryTest() { GSM testGSM = GSM.IPhone4s; testGSM.AddCall("0999-999-999", 2.3); testGSM.AddCall("0888-999-999", 12.4); testGSM.AddCall("0777-999-999", 4.34); testGSM.AddCall("0666-999-999", 8.2); testGSM.AddCall("0555-999-999", 11.2); Console.WriteLine("-------Showing added calls--------"); testGSM.ShowCallHistory(); Console.WriteLine("------Calculating total price for calls------"); double totalCallPrice = testGSM.CalculateCallsTotalPrice(); Console.WriteLine("{0:C}", totalCallPrice); Console.WriteLine("----Removing longest call and recalculating-----"); testGSM.RemoveLongestCallEntry(); testGSM.ShowCallHistory(); totalCallPrice = testGSM.CalculateCallsTotalPrice(); Console.WriteLine("{0:C}", totalCallPrice); Console.WriteLine("----Clearing call history-----"); testGSM.ClearCallHistory(); testGSM.ShowCallHistory(); }