AdventOfCode-Java VS aoc-2020

Java https://github.com/SimonBaars/AdventOfCode-Java/blob/master/src/main/java/com/sbaars/adventofcode/year21/days/Day17.java

Java Today was very easy, but it took me considerable effort to wrap my mind around the problem. I was almost about to do a multithreaded solution when I facepalmed and implemented what I actually had to implement.

Java

Java Fun day, I like space cards. I had minor Vietnam flashbacks to the spacecards of last year, but luckily it was nothing like that. Some takeaways:

I've tried it a few times and solutions were surprisingly elegant! E.g., 2020-01-p2.

Figured I'd post my benches as well, see below. Everything done in Rust (link to source).

Here's my day 24 in Rust, using SIMD as usual :) (and offset coordinate encoding to make a SIMD-friendly 2-D cell grid)

Borrowed both ideas in my version :) On my input your version runs at 3ms, mine in 1.5ms, so it might be faster on some inputs (link). I initially started with something similar to yours but then figured why not use 512-bit ints, so that the notion of 'head' and 'tail' disappears as your head then stays at position 0 (so, e.g., to remove a card, you just right-shift the whole bigint). Also used a tiny bit of simd along the way.

Part 1 + Part 2