Added a clarification.

You should make the test cases not run in time if the O(n) solution is not used.

I also think so, it's a minor quality duplicate. For this version, it would have been nice to include in the kata description the implementation of the Node, Edge, etc .

...there is something wrong with the submission tests. My submission gets stuck because the code is supposed to accept coordinates with... letters... in them?

Yes I did, thanks.

I agree. It also doesn't add anything to that example, other than wrapping the graph in objects. :-(

ah looks like it's way easier than i first thought. i think i'm getting the hang of it, thanks!

Good exercise, but I agree that a little clarification if also keys are to be replaced should be added as well as some more test cases (only 2 for now), so to diminish partial fulfillment.

Thanks! It occurred to me while trying to simplify the code.

@jakber, You should unmark this as a spoiler in case someone wants to solve it. It took me a few tries to figure out which character was the mistake. :-)

Thanks!

@OverZealous: a also used the even function in the example test fixture.