Solutions to the 2021 Advent of Code (https://adventofcode.com/2021/), in Rust. Trying to strike a balance between performance and ease-of-writing, erring on the side of performance where necessary.

Simple to use: just cargo test --release or cargo test -p day_1, for example. Some crates have Criterion benchmarks: cargo bench, or cargo bench -p day_1, for example.

I'm certainly no expert in Rust; don't assume I've done anything in a sane way.