- [itertools](https://crates.io/crates/itertools): Extends iterators with extra methods and adaptors. Frequently useful for aoc puzzles.

- [regex](https://crates.io/crates/regex): Official regular expressions implementation for Rust.

A curated list of popular crates can be found on [blessred.rs](https://blessed.rs/crates).

A curated list of popular crates can be found on [blessed.rs](https://blessed.rs/crates).

Do you have aoc-specific crate recommendations? [Share them!](https://github.com/fspoettel/advent-of-code-rust/edit/main/README.md)

- **Integer overflows:** This template uses 32-bit integers by default because it is generally faster - for example when packed in large arrays or structs - than using 64-bit integers everywhere. For some problems, solutions for real input might exceed 32-bit integer space. While this is checked and panics in `debug` mode, integers [wrap](https://doc.rust-lang.org/book/ch03-02-data-types.html#integer-overflow) in `release` mode, leading to wrong output when running your solution.

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advent_of_code::solution!(%DAY_NUMBER%);

pub fn part_one(input: &str) -> Option<u32> {

pub fn part_one(input: &str) -> Option<u64> {

None

}

pub fn part_two(input: &str) -> Option<u32> {

pub fn part_two(input: &str) -> Option<u64> {

None

}