I feel like there’s a solution that involves caching the paths from any node in the graph where the key is the node + whether or not you’ve already looped or not.
seems like a pretty well-defined method for doing it, most of the differences are going to be in how you pick the data types and organize the edges
Essentially a port of a solution shared by a friend (<https://todd.ginsberg.com/post/advent-of-code/2021/day12/>): <https://github.com/benknoble/advent2021/blob/main/day12/solution.rkt> Part2 is really slow on my input
<https://github.com/lojic/LearningRacket/blob/master/advent-of-code–2021/solutions/day12/day12.rkt|Day 12>
Day 13 spoilers
Today’s was really simple. I managed to score <500 on the global leaderboard for the first time this year.
Did mine initially with a bit-vector, but then thought a bit more and went back for sparse matrix:
https://github.com/massung/advent2021/blob/main/day13/day13.lisp
Not sure about anyone else, but one part of my input data was not down the middle, which caused a little bit of a headache using the bit-vectors, but was obviously a non-issue for the hash table.
This is the first advent puzzle I’ve done in 3 years that has been about “graphical” output that needed to be interpreted by me for the solution. I thought that was pretty cool.