c/aoc-2023
1
Fork 0
Code Issues Releases Activity

Day 4 cleanup

Browse Source
This commit is contained in:
Christian
2023-12-07 10:08:22 +01:00
parent 7c30d11783
commit 6ceb565e34
1 changed files with 13 additions and 31 deletions
Download Patch File Download Diff File Expand all files Collapse all files

44
src/bin/day04.rs
View File

@@ -4,7 +4,6 @@ use std::fs;
use std::collections::HashSet; use std::collections::HashSet;
use anyhow::{Context, Result}; use anyhow::{Context, Result};
use regex::Regex;
fn main() -> Result<()> { fn main() -> Result<()> {
let filename = env::args() let filename = env::args()
@@ -12,50 +11,33 @@ fn main() -> Result<()> {
.context("./day04 <path to puzzle input>")?; .context("./day04 <path to puzzle input>")?;
let input = fs::read_to_string(filename)?; let input = fs::read_to_string(filename)?;
let re = Regex::new(r"\d+")?;
let lines = input.lines().collect::<Vec<_>>(); let lines = input.lines().collect::<Vec<_>>();
let mut count: Vec<usize> = vec![1; lines.len()]; let mut count: Vec<usize> = vec![1; lines.len()];
let mut part1 = 0; let mut part1 = 0;
for (line_num, line) in lines.into_iter().enumerate() { for (line_num, line) in lines.into_iter().enumerate() {
let mut hs = HashSet::new();
let (_, card_text) = line.split_once(':').unwrap(); let (_, card_text) = line.split_once(':').unwrap();
let (winning, mine) = card_text.split_once('|').unwrap(); let (winning_str, mine_str) = card_text.split_once('|').unwrap();
let winning_nums = re let winning = winning_str
.find_iter(winning) .split_ascii_whitespace()
.map(|m| m.as_str().parse::<u32>().unwrap()); .map(|m| m.parse::<i32>().unwrap())
.collect::<HashSet<_>>();
let my_nums = re let mine = mine_str
.find_iter(mine) .split_ascii_whitespace()
.map(|m| m.as_str().parse::<u32>().unwrap()); .map(|m| m.parse::<i32>().unwrap());
for i in winning_nums { let num_matches = mine.filter(|n| winning.contains(n)).count();
hs.insert(i);
}
let mut num_matches: usize = 0;
for i in my_nums {
if hs.contains(&i) {
num_matches += 1;
}
}
for i in line_num + 1..line_num + num_matches + 1 {
if i >= count.len() {
break;
}
for i in (line_num + 1)..(line_num + num_matches + 1).min(count.len()) {
count[i] += count[line_num]; count[i] += count[line_num];
} }
if num_matches > 0 { if num_matches > 0 {
part1 += 1 << (num_matches - 1); part1 += 1 << (num_matches - 1);
} }
} }
let part2 = count.into_iter().sum::<usize>(); let part2 = count.into_iter().sum::<usize>();