aoc2020 VS aoc-clojure

https://github.com/haskelling/aoc2020/blob/main/AOC.hs#L285-L292

I sometimes used Parsec, and sometimes splitOn from Data.List.Split, but normally managed to get the parsing side working pretty quickly. My code is at https://github.com/haskelling/aoc2020 if you're interested.

Video walkthrough and code repo.

Code Repository: https://github.com/haskelling/aoc2020

Code: https://github.com/haskelling/aoc2020 Video: https://youtu.be/26EvM7WhjU8

Part 2: https://github.com/haskelling/aoc2020/blob/main/20b.hs

Code Repository: https://github.com/haskelling/aoc2020

By the way, my code for day 20 is already on GitHub.

As for the CS algorithms and concepts required, indeed many of the part 2s are for sure only really doable with university-level training. Fortunately, though, there are many universities that put their lectures online. One is MIT, and I would highly recommend watching MIT 6.006 and 6.046, available free on the MIT OpenCourseWare YouTube channel. The lectures on dynamic programming are particularly pertinent for both 7b and 10b. In fact, the solutions I had for both boiled down to the same algorithm: summarising a DAG (directed acyclic graph) from the leaves up, so I was able to reuse my code and solve 10b really quickly.

My AoC code is at https://github.com/haskelling/aoc2020 but I'm afraid it's not in Dart. I have to admit that I haven't actually done much Dart for a few years, so I saw your post as an opportunity to see if I could remember a bit. My code in all languages these days is now very much influenced by Haskell, which I'm using for AoC. If you're interested, I also have a video series about solving AoC2020 in Haskell: https://www.youtube.com/channel/UCcrYL-tiYTlULpi_BGB44QA/videos

They're not; line 20 is computing a mapping from cup to next cup, and they're using that to look the destination up on line 30. So this is already using direct lookups on a hashmap.

Clojure: https://github.com/mgrzeszczak/aoc-2020-clojure/blob/master/src/aoc_2020_clojure/day22.clj