aoc-clojure VS aoc

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

Code, such as it is, is checked in here.

Merry Christmas! As a simple Christmas Card, here's an input file for day 9's decoder that produces this scene.

Watching the Elves dance around till they all find a little space they can be happy in. Code's here on github

github

Probably not the most useful visualization, but I wanted to see what was going on. Lines represent the nodes being moved along the circular buffer, and the color of each node is the final position along the node. Code's here on github.

Took a stab at making a little compiler for Day 10 so I could draw my own messages. This is the result, though in theory it can draw out any 8 character message, within some limits. Code's here on github

Like most days the solution for this day is mostly stand alone Python code. For days that involve a visualization, there are two important caveats:

Watching a madman drag a rope around. Code is on github

Just some fun looking at a visualization of the size of the file system presented in the puzzle input, using a tool meant to help you visualize AWS S3 buckets. The code to dump out the input is a small addition to my puzzle solver.

github