Whew. I’m a few days late, but here are my solutions for day 24 and day 25.
I also finally managed to get day 21. I got part one using a list-based solution, but that was far too slow for part 2. I had to refactor to a nested map solution, which gave me an answer to part two in a reasonable amount of time.
Merry Christmas everyone! 
This was my first AoC, and I had a lot of fun doing it! Thanks everyone for sharing your solutions. We should do this again next year 
Merry Christmas!
Hey all,
I wrote up a quick post on a handful of things I learned during this year’s Advent of Code. There’s some high level information about problem solving in general, along with some detailed tidbits about Elixir and Erlang.
Hopefully someone can take something from it.