AdventOfCode VS advent-of-code

Here's an example implementation in Rust, using rayon's parallel iterators to automatically distribute the computation of a range of hashes over all available cores. It solves both parts together in around 3 seconds on my M2 MacBook Pro. Single-threaded, it takes around 25s in Rust and 35s in Python.

Here are mine: https://github.com/benediktwerner/AdventOfCode

I love doing optimizations like this but I don't really have enough time anymore to really do it. In 2020 I spent a fair amount of time writing super optimized solutions for the first 10 or so days (repo solving all those days together in 150us i.e. <1ms) but even back then, I eventually stopped since I had other things to do and it took more and more time as the days went on.

Python 3 116/125

Wow, my final solution looks almost exactly the same. Though I calculated my initial answers by hand.

That's certainly not necessary though and really not what makes most of the speed, especially for problems like today's. I don't really look at other leaderboard competitor's solutions much but at least my solutions (ranked ~20 today) are almost always completely vanilla Python (the only exception is networkx for the occasional graph problem but even that isn't really that much of a speedup if you know the common graph algorithms) and always self-contained.

Interesting approach. I guess mine could be considered a bit nicer, doing it recursively and returning the number to add to the left or right.

My priority Q/heap Dijkstra in Python runs just fine. I don't remember and can't check rn if it was instant or took a second but it definitely wasn't longer than that.

In my code I represented a quaternion as a four element list, and it can encode a 3D rotation around an axis. I wrote the basic functions for working with them almost straight from Wikipedia. There's only really four functions in my solution that use the basic functions: frame-forward, turn, rc-to-cube, and net-direction.

I spent a long time on this on Sunday but really enjoyed it. I've linked the code for the day above but I've split off the library functions into my general AoC repository, they're in zipper.lisp maybe.lisp and a couple of functions in monad.lisp.

I've been writing the parsing functions in a utility library for Advent of Code as I worked through all of the stars. The parser is here https://github.com/blake-watkins/advent-of-code/blob/main/parser.lisp