This was problem was very frustrating. More when I solved it and saw other people's solution. Most of them I tried them out and had no success because of timeout. After a lot of optimizations including caching results, using C arrays and a bit of memoization, I finally got the problem solved.

However that much work doesn't come close to other solutions, I have no idea how they got past the timeout issue without the optimizations.

Other than that, having to think so much about resources is a good experience. Even though frustrating, this kata is what fun coding is all about.