Advent of code 2024

Advent of Code is a yearly event, running since 2015. It is made by Eric Wastl, and it is “an Advent calendar of small programming puzzles”.

I had never heard of it until this year, when I started following the blog of Juha-Matti Santala, and saw him document his progress. I thought it would be fun – and I was right. I also thought that the practice of writing up how I came to the solutions was nice, and decided to do it as well. All of my notes on the puzzles can be found here: https://notes.adfoucart.be/aocode24. And all of my code, the good and the bad, is on my Gitlab.

One thing I really like about it is that there are basically no rules except the ones we bring with us. Eric posts a two-part puzzles every day, where you have to solve the first part in order to get the second part. You solve the puzzle by writing (or rather copy-pasting) a number into a box, and the only check that is made is if you have the right number. It doesn’t matter which language you used, or if your solution is clever, or efficient, or even would generalize to any other inputs than those he gave.

There is a leaderboard, but it is obviously just there for people who really want a leaderboard. The only metric used for it is how fast you solved the puzzle. I didn’t notice it was there until several days into the challenge.

So why do I do it? I decided to use it to get better at using the Python standard library efficiently, and to practice finding a good way to frame the problem so that the solution is generic and modular enough that, when part 2 is revealed, I can easily add to the existing code without modifying too many functions (ideally, none).

Sometimes it works, sometimes not. We’re halfway through, and I’m reasonably satisfied with most of my solutions so far. If you’re into that kind of things, I highly encourage doing it. All of the puzzles from the previous years are available as well.