A simple elevator

[mohayemin]

Overview

An elevator responds to call based on where an elevator is currently located and in which direction it is going.

Example

Assume that the elevator is at level 2 and going to level 5.

• If the up button of level 3 is pressed - it will stop at level 3 and then continue to level 5.
• If the down button of level 3 is pressed - it will go to level 5 without stopping, then come back to level 3 and stop.

Assumptions

• The elevator is for a 5 level building.
• The elevator has three movement types: up, down, stopped.
• The elevator can be at a specific level at a time, no need to consider that it can be in between two levels.
• The elevator can be called only from outside buttons (up/down).
• A single elevator is being controlled by the buttons.
• No need to consider calls from multiple places.
• No need to consider concurrency and multi-threading.

Task

• Write an Elevator class.
• Write a call method in the elevator class, which takes input a Button, using which it has been called.
• The call method should return true if the elevator will stop directly, false if it will first move to its current destination and then accept the call.
• Feel free to write additional classes that might be required.

Learning goal

• Encapsulation

Notes

• UI Simulation is not the goal of this problem.

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