static void Main(string[] args)
{
DigitalPhone myDigitalPhone = new DigitalPhone();
myDigitalPhone.Ring();
myDigitalPhone.VoiceMail();
DigitalCellPhone myDigitalCellPhone = new DigitalCellPhone();
myDigitalCellPhone.Ring();
myDigitalCellPhone.VoiceMail();
}
static void Main(string[] args)
{
ElectricPhone myPhone = new ElectricPhone();
myPhone.Ring();
DigitalPhone myDigitalPhone = new DigitalPhone();
myDigitalPhone.Ring();
TalkingPhone myTalkingPhone = new TalkingPhone();
myTalkingPhone.Ring();
}