If the appointment is an emergency, the schedule is cleared of all appointments that have a time conflict with the given appointment, and the appointment is added to the schedule. If the appointment is not an emergency, the schedule is checked for any conflicting appointments. If there are no conflicting appointments, the given appointment is added to the schedule. Method addAppt returns true if the appointment was added to the schedule; otherwise, it returns false.

a) addAppointment(boolean emergency)
b) scheduleAppointment(boolean emergency)
c) confirmAppointment(boolean emergency)
d) addAppt(boolean emergency)