Advent of Code 2021

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And day 2 was fun, I decided to make a ‘proper’ set of types of it instead of just churning in place, less efficient then it could be for sure, but fast enough to run it dozens of times in the span of a single eyeblink so meh, lol:

❯ cargo run --release -- -v 2021 2            
    Finished release [optimized] target(s) in 0.05s
     Running `target/release/advent_of_code -v 2021 2`
Step 1: 1250395
Step 2: 1451210346
_Day2 Time Taken: 90.003µs_
_Time Taken: 92.593µs_

And the code (also available on my prior post github link), with still probably waaaay too much error checking but eh, I almost even used checked_add/sub instead of the default overflowing +/- but considered even that ‘too’ excessive for this, lol:

use crate::aoc::helpers::*;
use crate::AocApp;
use anyhow::Context;
use clap::Parser;
use std::num::NonZeroU8;
use std::path::PathBuf;

#[derive(Debug, Parser)]
pub struct Day2 {
	/// The input file of "commands"
	#[clap(default_value = "inputs/2021/day2.input")]
	pub input_file: PathBuf,
}

enum Commands {
	Forward(NonZeroU8),
	Down(NonZeroU8),
	Up(NonZeroU8),
}

#[derive(Default)]
struct Pos {
	depth: u32,
	fore: u32,
	aim: u32,
}

impl Pos {
	fn solution(&self) -> u32 {
		self.depth * self.fore
	}
}

impl Day2 {
	pub fn run(&self, _app: &AocApp) -> anyhow::Result<()> {
		let commands = map_trimmed_nonempty_lines_of_file(&self.input_file, |line| {
			match line
				.split_once(' ')
				.context("input is not a command then space then a number")?
			{
				("forward", n) => Ok(Commands::Forward(
					n.parse().context("input is not a number")?,
				)),
				("down", n) => Ok(Commands::Down(n.parse().context("input is not a number")?)),
				("up", n) => Ok(Commands::Up(n.parse().context("input is not a number")?)),
				_ => anyhow::bail!("input is not a valid command of forward|down|up then a number"),
			}
		})?;
		println!(
			"Step 1: {}",
			commands
				.iter()
				.fold(Pos::default(), |mut pos, cmd| {
					match cmd {
						Commands::Forward(n) => pos.fore += n.get() as u32,
						Commands::Down(n) => pos.depth += n.get() as u32,
						Commands::Up(n) => pos.depth -= n.get() as u32,
					}
					pos
				})
				.solution()
		);
		println!(
			"Step 2: {}",
			commands
				.iter()
				.fold(Pos::default(), |mut pos, cmd| {
					match cmd {
						Commands::Down(n) => pos.aim += n.get() as u32,
						Commands::Up(n) => pos.aim -= n.get() as u32,
						Commands::Forward(n) => {
							pos.fore += n.get() as u32;
							pos.depth += pos.aim * n.get() as u32;
						}
					}
					pos
				})
				.solution()
		);

		Ok(())
	}
}

EDIT: And here’s the full output of run-all so far:

OvermindDL1’s Advent Of Code

Year2015

Year2015 Time Taken: 40ns

Year2016

Year2016 Time Taken: 30ns

Year2017

Year2017 Time Taken: 30ns

Year2016

Year2016 Time Taken: 40ns

Year2019

Year2019 Time Taken: 30ns

Year2020

Year2020 - Day1

Step 1: 731731
Step 2: 116115990
Day1 Time Taken: 96.843µs

Year2020 - Day2

Step 1: 515
Step 2: 711
Day2 Time Taken: 214.024µs

Year2020 - Day3

Step 1: 250
Step 2: 1592662500
Day3 Time Taken: 134.3µs

Year2020 - Day4

Step 1: 206
Step 2: 123
Day4 Time Taken: 227.134µs
Year2020 Time Taken: 711.038µs

Year2021

Year2021 - Day1

Step 1: 1448
Step 2: 1471
Day1 Time Taken: 110.992µs

Year2021 - Day2

Step 1: 1250395
Step 2: 1451210346
Day2 Time Taken: 80.384µs
Year2021 Time Taken: 207.505µs
All Time Taken: 941.942µs

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