static void Main(string[] args)
{
CountDownTimer countDownTimer = new CountDownTimer();
Oven oven = new Oven(countDownTimer);
Microwave microwave = new Microwave(countDownTimer);
countDownTimer.SimulateNewTimer(1000);
countDownTimer.SimulateNewTimer(1500);
oven.Unregister(countDownTimer);
countDownTimer.SimulateNewTimer(1000);
}