advent-of-code-2022 VS AdventOfCode

The code is horrible, but performance is great. The basic idea of the algorithm is to consider all the valves we can move to. We compute how long it will take to move to a valve, and we also precompute how much pressure will be released in total by this valve using the remaining time. Then, if there are paths that have an equal distance, we only have to consider the path that has the highest potential pressure release. This drastically reduces the iterations needed, hence the low runtime. Also, the distances are not precomputed, but they are cached. This is more efficient, since we don't need all paths (for example we can skip all paths that have 0 flow rate, as we will never move to them, only pass them).

Just a basic BFS. My part 2 ran in 1.77 seconds.

Here's my solution. It's a bit of a janky script.

Yet another Python solution to part 2. My Python code isn't the best but I haven't seen many solutions that detect cycles programmatically.

There's nothing particularly nice about my Python solution but in case anyone's interested here it is. I find all points' shortest paths using floodfill and a loop because I couldn't recall Floyd-Warshall. And then it's a DFS, branching every turn when the human or elephant can make a choice to move to another valve and open it. Debugging was tricky.

You can check my solutions from last year https://github.com/WilliamLP/AdventOfCode/tree/master/2021 I made it up to day 14 / 17 and used that WITH RECURSIVE / UNNEST / ARRAY_AGG pattern a lot.

I got there, but math! It took a few hours, more along the lines of a weekend project than a quick puzzle! The hardest part is working with the 24 orientations I think. I needed to dust off a little bit of linear algebra and used matrices. There are 6 permutations of the 3 coordinates, and 8 flips (+- on each axis). Composing those gives 48 transformations but half of them are the wrong chirality (mirror image) so we want only the half with determinant equal one. After that it's just a bunch of picky loops and debugging. https://github.com/WilliamLP/AdventOfCode/blob/master/2021/day19.py