exercism fetch ruby dominoes


Make a chain of dominoes.

Compute a way to order a given set of dominoes in such a way that they form a correct domino chain (the dots on one half of a stone match the dots on the neighbouring half of an adjacent stone) and that dots on the halfs of the stones which don't have a neighbour (the first and last stone) match each other.

For example given the stones [2|1], [2|3] and [1|3] you should compute something like [1|2] [2|3] [3|1] or [3|2] [2|1] [1|3] or [1|3] [3|2] [2|1] etc, where the first and last numbers are the same.

For stones [1|2], [4|1] and [2|3] the resulting chain is not valid: [4|1] [1|2] [2|3]'s first and last numbers are not the same. 4 != 3

Some test cases may use duplicate stones in a chain solution, assume that multiple Domino sets are being used.

For installation and learning resources, refer to the exercism help page.

For running the tests provided, you will need the Minitest gem. Open a terminal window and run the following command to install minitest:

gem install minitest

If you would like color output, you can require 'minitest/pride' in the test file, or note the alternative instruction, below, for running the test file.

Run the tests from the exercise directory using the following command:

ruby dominoes_test.rb

To include color from the command line:

ruby -r minitest/pride dominoes_test.rb

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.