The comments here are the kind of bs that makes algorithm study impossible. This kata is very easy if you know "how" to work out problems like this. I wish more people would comment on the foundations to the "how" of a problem rather than just simple stating "oh this is easy, but I don't want to give out hints blah blah blah" nonsense. You can help people become better problem solvers by giving them foundational "how to" without giving spoilers. Sites like this shouldn't be a stump the chump type site. So here is a foundational concept that you should learn so that you can solve problems that involve circular reasoning. It's called modular arithmetic. Google it, practice what you learned, then come back and solve this kata.

I retrained on this kata and copy/pasted this solution. It doesn't work unless I put the boolean values in quotes.