2023 day4/rust: add solution

This commit is contained in:
Xiretza 2023-12-04 17:31:50 +00:00
parent a4568c199b
commit 3109623176
4 changed files with 86 additions and 0 deletions

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@ -0,0 +1,9 @@
[package]
name = "rust_2023_04"
version = "0.1.0"
edition = "2021"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]
aoc = { path = "../../../common/rust" }

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@ -0,0 +1,69 @@
#![warn(clippy::pedantic)]
use std::{io::stdin, num::NonZeroU32};
#[derive(Debug, Clone, PartialEq, Eq)]
struct Card {
winning: Vec<usize>,
found: Vec<usize>,
}
impl Card {
pub fn parse(s: &str) -> Self {
fn get_numbers(s: &str) -> Vec<usize> {
s.split(' ')
.filter(|s| !s.is_empty())
.map(|n| n.parse().unwrap())
.collect()
}
let (_id, numbers) = s.split_once(": ").unwrap();
let (winning, found) = numbers.split_once(" | ").unwrap();
let winning = get_numbers(winning);
let found = get_numbers(found);
Self { winning, found }
}
pub fn num_matching(&self) -> usize {
self.found
.iter()
.filter(|n| self.winning.contains(n))
.count()
}
pub fn exp_score(&self) -> usize {
if let Some(matching) = NonZeroU32::new(u32::try_from(self.num_matching()).unwrap()) {
2_usize.pow(matching.get() - 1)
} else {
0
}
}
pub fn recursive_score(&self, previous: &[usize]) -> usize {
1 + previous
.iter()
.rev()
.take(self.num_matching())
.sum::<usize>()
}
}
fn main() {
let cards: Vec<Card> = stdin().lines().map(|l| Card::parse(&l.unwrap())).collect();
println!("{}", cards.iter().map(Card::exp_score).sum::<usize>());
let recursive_score: usize = cards
.iter()
.rev()
.fold(Vec::new(), |mut previous, card| {
let score = card.recursive_score(&previous);
previous.push(score);
previous
})
.iter()
.sum();
println!("{recursive_score}");
}

7
Cargo.lock generated
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@ -663,6 +663,13 @@ dependencies = [
"enum-map", "enum-map",
] ]
[[package]]
name = "rust_2023_04"
version = "0.1.0"
dependencies = [
"aoc",
]
[[package]] [[package]]
name = "rust_2023_05" name = "rust_2023_05"
version = "0.1.0" version = "0.1.0"

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@ -29,5 +29,6 @@ members = [
"2022/day18/rust", "2022/day18/rust",
"2023/day1/rust", "2023/day1/rust",
"2023/day2/rust", "2023/day2/rust",
"2023/day4/rust",
"2023/day5/rust", "2023/day5/rust",
] ]