nebkor/aoc2024
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Compare commits

..

No commits in common. "0a0a4ec5d90c6d6928433c80fa61b89be655d1ab" and "81f7933cc0e6f1db78142d6b99c1d29af2a8fbd7" have entirely different histories.
0a0a4ec5d9 ... 81f7933cc0

1 changed files with 21 additions and 44 deletions

65
day10/src/main.rs
View file

@ -1,60 +1,45 @@
use std::collections::{HashSet, VecDeque}; use std::collections::HashSet;
fn main() { fn main() {
let input = std::fs::read_to_string("input").unwrap(); let input = std::fs::read_to_string("input").unwrap();
let grid = Grid::new(&input); let grid = Grid::new(&input);
println!("{}", pt1(&grid)); println!("{}", pt1(&grid));
println!("{}", pt2(&grid));
} }
fn pt1(grid: &Grid) -> usize { fn pt1(grid: &Grid) -> usize {
score(grid) dfs(grid)
} }
fn pt2(grid: &Grid) -> usize { fn dfs(grid: &Grid) -> usize {
rank(grid)
}
fn score(grid: &Grid) -> usize {
let mut total = 0; let mut total = 0;
for head in grid.heads.iter() { for head in grid.heads.iter() {
let mut htotal = 0; let mut processed = HashSet::new();
let mut q = Vec::new(); let mut q = Vec::new();
let mut nines = HashSet::new();
q.push(*head); q.push(*head);
while let Some(current) = q.pop() { while let Some(current) = q.pop() {
if grid.get(&current).unwrap() == 9 && nines.insert(current) { if !processed.contains(&current) {
htotal += 1; q.push(current);
} }
let mut do_top = true;
let nexts = grid.next_step(&current); let nexts = grid.next_step(&current);
for next in nexts.iter() { for next in nexts.iter() {
q.push(*next); if !processed.contains(next) {
q.push(*next);
do_top = false;
}
}
if do_top {
let _ = q.pop();
processed.insert(current);
if grid.get(&current).unwrap() == 9 {
total += 1;
}
} }
} }
total += htotal;
}
total
}
fn rank(grid: &Grid) -> usize {
let mut total = 0;
for head in grid.heads.iter() {
let mut htotal = 0;
let mut q = VecDeque::new();
q.push_back(*head);
while let Some(current) = q.pop_front() {
if grid.get(&current).unwrap() == 9 {
htotal += 1;
}
let nexts = grid.next_step(&current);
for next in nexts.iter() {
q.push_back(*next);
}
}
total += htotal;
} }
total total
@ -143,8 +128,6 @@ impl Grid {
out out
} }
// returns list of neighbor nodes in a dag where the edges are all one step in
// distance
fn next_step(&self, loc: &Loc) -> Vec<Loc> { fn next_step(&self, loc: &Loc) -> Vec<Loc> {
let alt = self.rows[loc.row][loc.col]; let alt = self.rows[loc.row][loc.col];
let target = alt + 1; let target = alt + 1;
@ -186,10 +169,4 @@ mod test {
let g = Grid::new(INPUT); let g = Grid::new(INPUT);
assert_eq!(36, pt1(&g)); assert_eq!(36, pt1(&g));
} }
#[test]
fn p2() {
let g = Grid::new(INPUT);
assert_eq!(81, pt2(&g));
}
} }