/parking-lot

Primary LanguageRuby

Parking Lot

Solution attempted by Sue Zheng Hao for Gojek take-home test.

Setup

Install Ruby if it is not already installed. Then run ./bin/setup to setup and run the test suite.
If there are any problems, please check the Known Issues.

Commands

Create the parking lot

Input: create_parking_lot 6 - Create a parking lot with 6 slots

Success Response: Created a parking lot with 6 slots

Failure Response: Invalid number of slots - If argument was invalid (e.g. negative number or not a number)

Failure Response: Parking lot already exists - If parking lot was already created

Park a car

Input: park KA-01-HH-1234 White - Attempt to park a white car with registration number KA-01-HH-1234.
Assumptions: No duplicate registration numbers exist. Registration numbers do not contain whitespace characters.

Success Response: Allocated slot number: 1 - Car allocated to an available slot 1

Failure Response: Sorry, parking lot is full - Parking lot is fully occupied

Leave the parking lot

Input: leave 4 - Car parked in slot 4 leaves the parking lot

Success Response: Slot number 4 is free - Car has left the parking lot and slot 4 is now free

Failure Response: No car in slot number 4 - There was no car in slot 4

Failure Response: Invalid slot number - If argument was invalid (e.g. negative number or not a number)

Check parking lot status

Input: status

Success Response:

Slot No.    Registration No    Colour
1           KA-01-HH-1234      White
2           KA-01-HH-3141      Black
3           KA-01-HH-9999      White

Find registration numbers of all cars of a particular colour

Input: registration_numbers_for_cars_with_colour White

Success Response: KA-01-HH-1234, KA-01-HH-9999

Failure Response: Not found

Find slot numbers of all slots where a car of a particular colour is parked.

Input: slot_numbers_for_cars_with_colour White

Success Response: 1, 3

Failure Response: Not found

Find slot number in which a car with a given registration number is parked.

Input: slot_number_for_registration_number KA-01-HH-1234

Success Response: 1

Failure Response: Not found

Exit the program

Input: exit

Design Assumptions

  • Car registration number & colour do not contain spaces
  • Car registration number is case insensitive (e.g. 'ka-01' == 'KA-01')
  • Car registration number has a max length of 18 characters (following given status output format)

Possible Improvements

  • The 3 find commands can be sped up by implementing a hashmap keyed by the car colour/registration number. Currently, they retrieve the result in linear time by checking every slot.
  • The park command tries to park the car in the nearest free slot as defined in the question. Allowing the user to specify an alternative strategy may be useful.

Known Issues

The test suite may fail on systems that use rbenv with an error like this: rbenv: bundle: command not found.
If you use rbenv, please run the following commands first:

cd functional_spec
rbenv versions
rbenv local <ruby version available in rbenv>