Parking Lot Problem Solution

Problem Statement: A Parking lot can hold up to 'n' cars at any given point in time. Each slot is given a number starting at 1 increasing with increasing distance from the entry point in steps of one.

When a car enters the parking lot, a ticket issued to the driver. The ticket issuing process includes documenting fallowing:

• the registration number (number plate).
• the colour of the car.
• allocating an available parking slot to the car.

Note: The customer should be allocated a parking slot which is nearest to the entry.

At the exit, the customer returns the ticket which then marks the slot they were using as being available.

Due to government regulation, the system should provide:

• Registration numbers of all cars of a particular colour.
• Slot number in which a car with a given registration number is parked.
• Slot numbers of all slots where a car of a particular colour is parked.

$ create_parking_lot 6
Created a parking lot with 6 slots
Allocated slot number: 1
Allocated slot number: 2
Allocated slot number: 3
Allocated slot number: 4
Allocated slot number: 5
Allocated slot number: 6
$ park KA-01-HH-1234 White
Allocated slot number: 1
$ park KA-01-HH-9999 White
Allocated slot number: 2$ park KA-01-BB-0001 Black
Allocated slot number: 3
$ park KA-01-HH-7777 Red
Allocated slot number: 4
$ park KA-01-HH-2701 Blue
Allocated slot number: 5
$ park KA-01-HH-3141 Black
Allocated slot number: 6
$ leave 4
Slot number 4 is free
$ status
Slot No.    Registration No    Colour
1           KA-01-HH-1234      White
2           KA-01-HH-9999      White
3           KA-01-BB-0001      Black
5           KA-01-HH-2701      Blue
6           KA-01-HH-3141      Black
$ park KA-01-P-333 White
Allocated slot number: 4
$ park DL-12-AA-9999 White
Sorry, parking lot is full
$ registration_numbers_for_cars_with_colour White
KA-01-HH-1234, KA-01-HH-9999, KA-01-P-333
$ slot_numbers_for_cars_with_colour White
1, 2, 4
$ slot_number_for_registration_number KA-01-HH-3141
6
$ slot_number_for_registration_number MH-04-AY-1111
Not found
$ exit

Setup

First, install Ruby. Then run the following commands under the functional_spec dir.

functional_spec $ ruby -v # confirm Ruby present
ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-darwin17]
functional_spec $ gem install bundler # install bundler to manage dependencies
Successfully installed bundler-1.16.1
Parsing documentation for bundler-1.16.1
Done installing documentation for bundler after 2 seconds
1 gem installed
functional_spec $ bundle install # install dependencies
...
...
Bundle complete! 3 Gemfile dependencies, 8 gems now installed.
Use `bundle info [gemname]` to see where a bundled gem is installed.
functional_spec $ 

Usage

You can run the following commands under the parking_lot dir to make executable file.

parking_lot $ chmod +x bin/parking_lot

Then run the full suite from parking_lot by doing

parking_lot $ bin/parking_lot file_input.txt # file_input.txt is a file located in same dir, you can specify file name with file path

You can execute run the program and launch the shell

parking_lot $ bin/parking_lot