Awesome

Advent of Code

Complete 2023 to 2015 entries written in Rust for the annual Advent of Code challenge, solving 450 stars in less than 1 second.

Features

• Each solution uses the most efficient algorithms to the best of my knowledge.
• Self contained depending only on the std Rust library. No use of unsafe features.
• Consistently formatted with rustfmt and linted by clippy.
• Thoroughly commented with rustdoc generated documentation online.
• Test coverage with continuous integration provided by GitHub Actions.

Quickstart

Input

Place input files in input/yearYYYY/dayDD.txt including leading zeroes. For example:

• input/year2015/day23.txt
• input/year2023/day02.txt

Run

• Everything cargo run
• Specific year cargo run year2023
• Specific day cargo run year2023::day01
• Release profile (faster) cargo run --release
• Optimized for current CPU architecture (fastest) RUSTFLAGS="-C target-cpu=native" cargo run --release

Test

• Everything cargo test
• Specific year cargo test year2023
• Specific day cargo test year2023::day01
• Show STDOUT for debugging cargo test -- --nocapture

Benchmark

• Everything cargo bench
• Specific year cargo bench year2023
• Specific day cargo bench year2023::day01

Document

• Build docs including private items cargo doc --document-private-items
• Build doc then open HTML landing page cargo doc --document-private-items --open

Miscellaneous

• Code quality lints cargo clippy
• Consistent code formatting cargo fmt

Performance

Benchmarks are measured using the built-in cargo bench tool run on an Apple M2 Max. All 225 solutions from 2023 to 2015 complete sequentially in 579 milliseconds. Interestingly 84% of the total time is spent on just 9 solutions. Performance is reasonable even on older hardware, for example a 2011 MacBook Pro with an Intel i7-2720QM processor takes 3.5 seconds to run the same 225 solutions.

2023

2022

2021

2020

2019

2018

2017

2016

2015