MBTA Practice

To start

Fork, clone, branch (practice) and bundle install

Objectives

• Practice with classes, methods, and collections.
• You should submit a pull request for this practice, but it is not required.

Activity

• Create a class in lib/practice.rb with a method stops_between_stations to calculate the number of stops between stations on the "MBTA". Write additional classes and or methods as needed.
• The method takes the line and stop name that a rider is getting on at and the line and stop name that a rider is getting off at and returns the total number of stops for the trip.
• When MBTA::Subway::System.new is called, its initialize method should store all the information needed in stops_between_stations.

There are 3 subway lines:

• The Red line has the following stops: South Station, Park Street, Kendall, Central, Harvard, Porter, Davis, Alewife
• The Green line has the following stops: Government Center, Park Street, Boylston, Arlington, Copley, Hynes, Kenmore
• The Orange line has the following stops: North Station, Haymarket, Park Street, State, Downtown Crossing, Chinatown, Back Bay, Forest Hills
• All 3 subway lines intersect at Park Street, but there are no other intersection points. Some of this MBTA is fictionalized.

Checking your solution

Run bin/rake test.

Hints

• Assume good input. Your function need not check the validity of the line or stop name.
• Think about where to store initialization data.
• Consider diagramming the lines by sketching out the subway lines and their stops and intersection.
• The key to the practice is to find the intersection of the lines at Park Street.
• Solve an easier problem first.

Bonus

Think about adding Haymarket before Government Center on the Green line then try to find a solution when there are multiple intersections. Is there a way to decide if a particular solution is "correct"?

This bonus is completely optional and does not have tests, yet.

Tasks

Developers should run these often!

• bin/rake nag (or bundle exec rake nag): runs code quality analysis tools on your code and complains.
• bin/rake test (or bundle exec rake test): runs automated tests.
• bin/rake will run both nag and test

License

1. All content is licensed under a CC­BY­NC­SA 4.0 license.
2. All software code is licensed under GNU GPLv3. For commercial use or alternative licensing, please contact legal@ga.co.