Day 8: Resonant Collinearity
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FAQ
- What is this?: Here is a post with a large amount of details: https://programming.dev/post/6637268
- Where do I participate?: https://adventofcode.com/
- Is there a leaderboard for the community?: We have a programming.dev leaderboard with the info on how to join in this post: https://programming.dev/post/6631465
2 points
I also did it in Rust, though mine is quite a bit more verbose than yours :). https://gitlab.com/bricka/advent-of-code-2024-rust/-/blob/main/src/days/day08.rs?ref_type=heads
Have you considered using a HashSet<(usize, usize)> to store the visited locations instead of a 2d vector?
1 point
I try to use Vecs instead of HashSets and maps whenever the key domain is reasonably small (just the grid in this case), simply because in the end direct memory access is a lot faster than always hashing values.
But looking at this case again, it is certainly a lot easier to have just antinodes.len() at the end instead of counting all true values. This datastructure is also not really performance-critical, so a HashSet is probably the cleaner choice here.
