This program is a java applet which simulates the operation of a lift which has a capacity of one person. The lift only moves when necessary and it starts the day waiting with its doors closed on the building's first floor. Number of floors (Max. is 5, Min is 2) can be entered by the user.

*Instructions:

(1) Once the applet runs, the user can do 3 things:

      -click the "New Arrival" button to get a person to the lift.

      -enter the text field "Number of levels" to change the levels (2-5) of the building.

      -click the "Silent" button to switch to "no sound" mode.

(2) After the person gets in, he appears inside the lift on the right-hand side.

(3) User should choose the destination floor for the person by pressing the floor button inside the lift.

(4) The person will then leave on the destination floor when the lift gets there.

(5) User repeats the process from (1).

*Notes:

(0) Floor with Purple color is where the lift locates currently.

(1) User can only create one person at a time in the building. 

(2) User cannot change the level of building when there is a person in the lift or building. 

(3) After inputting the level of building, user must press [ENTER].

(4) After the person left the lift, the door of the lift still opens. 

(5) If user inputs invaild words or the number is out of range, then an error sound will be played. 

(6) If the number of the level has changed, the lift will return to building's first floor.

(7) User can choose the same destination floor as the person's arrival floor.

(8) Enlarge to maximum size of the browser to see the button 'Silent'.