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#![allow(dead_code)]
#![allow(unused_variables)]
use advent_of_code::prelude::*;
pub fn parse(fh: File) -> Result<Vec<(i64, i64, i64)>> {
Ok(parse::raw_lines(fh)
.map(|s| {
let mut parts = s.split(',');
(
parts.next().unwrap().parse().unwrap(),
parts.next().unwrap().parse().unwrap(),
parts.next().unwrap().parse().unwrap(),
)
})
.collect())
}
pub fn part1(points: Vec<(i64, i64, i64)>) -> Result<i64> {
let mut total = 0;
for p in &points {
let mut area = 6;
for neighbor in [
(p.0 - 1, p.1, p.2),
(p.0 + 1, p.1, p.2),
(p.0, p.1 - 1, p.2),
(p.0, p.1 + 1, p.2),
(p.0, p.1, p.2 - 1),
(p.0, p.1, p.2 + 1),
] {
if points.contains(&neighbor) {
area -= 1;
}
}
total += area;
}
Ok(total)
}
pub fn part2(points: Vec<(i64, i64, i64)>) -> Result<i64> {
let mut all_neighbors = HashSet::new();
for p in &points {
for neighbor in [
(p.0 - 1, p.1, p.2),
(p.0 + 1, p.1, p.2),
(p.0, p.1 - 1, p.2),
(p.0, p.1 + 1, p.2),
(p.0, p.1, p.2 - 1),
(p.0, p.1, p.2 + 1),
] {
if !points.contains(&neighbor) {
all_neighbors.insert(neighbor);
}
}
}
let bounds = (
(points.iter().map(|p| p.0).min().unwrap() - 1)
..=(points.iter().map(|p| p.0).max().unwrap() + 1),
(points.iter().map(|p| p.1).min().unwrap() - 1)
..=(points.iter().map(|p| p.1).max().unwrap() + 1),
(points.iter().map(|p| p.2).min().unwrap() - 1)
..=(points.iter().map(|p| p.2).max().unwrap() + 1),
);
let mut visited = HashSet::new();
let mut to_visit =
vec![(*bounds.0.start(), *bounds.1.start(), *bounds.2.start())];
while let Some(p) = to_visit.pop() {
visited.insert(p);
let neighbors = [
(p.0 - 1, p.1, p.2),
(p.0 + 1, p.1, p.2),
(p.0, p.1 - 1, p.2),
(p.0, p.1 + 1, p.2),
(p.0, p.1, p.2 - 1),
(p.0, p.1, p.2 + 1),
];
to_visit.extend(
neighbors
.iter()
.filter(|p| in_bounds(**p, &bounds))
.filter(|p| !visited.contains(p))
.filter(|p| !points.contains(p)),
)
}
let mut total = 0;
for p in &points {
let mut area = 6;
for neighbor in [
(p.0 - 1, p.1, p.2),
(p.0 + 1, p.1, p.2),
(p.0, p.1 - 1, p.2),
(p.0, p.1 + 1, p.2),
(p.0, p.1, p.2 - 1),
(p.0, p.1, p.2 + 1),
] {
if points.contains(&neighbor) || !visited.contains(&neighbor) {
area -= 1;
}
}
total += area;
}
Ok(total)
}
fn in_bounds(
p: (i64, i64, i64),
bounds: &(
std::ops::RangeInclusive<i64>,
std::ops::RangeInclusive<i64>,
std::ops::RangeInclusive<i64>,
),
) -> bool {
bounds.0.contains(&p.0)
&& bounds.1.contains(&p.1)
&& bounds.2.contains(&p.2)
}
#[test]
fn test() {
assert_eq!(
part1(parse(parse::data(2022, 18).unwrap()).unwrap()).unwrap(),
4608
);
assert_eq!(
part2(parse(parse::data(2022, 18).unwrap()).unwrap()).unwrap(),
2652
);
}
|
