Draw the state chart of the elevator room object :

An elevator room is part of an elevator system. This object is by default in stop state with doors closed. If the user press the floor button and the elevator room is in the same floor, the elevator room will open doors. If the user press the floor button and the elevator room is not in the same floor, the elevator room will keep moving until it reaches the requested floor, then it will open doors. If doors are open, it will close automatically after 1 minute.