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2024: Add solution for Day 8
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‎2024/Cargo.lock‎

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‎2024/Cargo.toml‎

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@@ -25,6 +25,7 @@ members = [
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"day23",
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"day24",
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"day25",
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"lib",
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]
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exclude = []
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resolver = "2"

‎2024/README.md‎

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@@ -17,7 +17,7 @@ cargo run --bin day01
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5. [Print Queue](day05) 🌟🌟
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6. [Guard Gallivant](day06) 🌟🌟
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7. [Bridge Repair](day07) 🌟🌟
20-
8. [](day08)
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8. [Resonant Collinearity](day08) 🌟🌟
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9. [](day09)
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10. [](day10)
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11. [](day11)

‎2024/day08/Cargo.toml‎

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@@ -6,3 +6,4 @@ edition = "2021"
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# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
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[dependencies]
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lib = { path = "../lib" }

‎2024/day08/example1.txt‎

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............
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........0...
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.....0......
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.......0....
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....0.......
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......A.....
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............
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............
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........A...
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.........A..
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............
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............

‎2024/day08/input.txt‎

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.....................U.........w..................
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l.................................................
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...........o.a................U...w...............
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............................................W.....
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..........T....................s.............7....
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.............................................W....
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.........T..............4....n.d.H.........5......
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......T.....oj...U.....n...w......H...........z...
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.G..x..........................E.....V..H.........
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.........a....................d....s.......7w.....
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...j....r.............o.............V.......d...W.
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.......r..J.Goa.U...............n................z
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.........Jj.........M..........Pv.................
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...J...........t..3..M..............sLV...........
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...................t................n.............
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....r...........X...........M........v............
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...x....t......I......a.PM...............W........
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...........1.Bj....I........vO.h.dL...............
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.........6....Rr......B...X........h..5v.L..z.....
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......1G...........x.....3B.......5...............
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.................B....0..........4..E.............
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.....................X.....5..h....P....f.....D...
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.......1........J.....eK..........................
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..................I....R....K...........k.........
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......G..................O........................
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...........H...9...............K8.P.4..k..E.......
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............1....3.............8.F.............f..
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.........................4........................
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.l...........X............9.......................
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....N.................R...t.e.....................
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...g............3..R.........e....h.........f.....
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...........................e......i...............
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................2...I.7..9..O.....s.........k.....
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....................6...9E.............F..O.......
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........................KN........................
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.......g......................Z.........F..f...Y..
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...........................A....i.................
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...........6g...b........8.......y.....S..........
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..l.....6.....m...............8...................
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....u..m...b...............p...A..................
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..............b.p........................k........
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....m......2...........Z..y....i..................
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........g2.....b.........i....D..ZF...............
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......2.0...........p............N..........A.....
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...m.............S...y........A...Z...N...........
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..S..l..........................................Y.
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........S....0u.................y......DY.........
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...........0.........................D............
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.................u...................p...Y........
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.......u..........................................

‎2024/day08/src/main.rs‎

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@@ -2,12 +2,18 @@
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//! https://adventofcode.com/2024/day/8
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use std::{fs, io};
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use std::collections::{BTreeMap, BTreeSet};
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use std::ops::Range;
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use std::path::Path;
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9+
use lib::vector::Vector;
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type Vec2 = Vector<i32, 2>;
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fn main() {
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let input = Input::from_file(format!("{}/input.txt", env!("CARGO_MANIFEST_DIR"))).expect("failed to read input");
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//let input = Input::from_file(format!("{}/example1.txt", env!("CARGO_MANIFEST_DIR"))).expect("failed to read input");
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println!("{input:?}");
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//println!("{input:?}");
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// Part 1
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println!("Part 1: {}", part1(&input));
@@ -17,24 +23,119 @@ fn main() {
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}
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fn part1(input: &Input) -> usize {
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0
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let mut freqs: BTreeMap<_, Vec<_>> = BTreeMap::new();
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for (pos, c) in input.antennas.iter() {
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freqs.entry(*c).or_default().push(*pos);
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}
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let mut antinodes = BTreeSet::new();
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for (_, positions) in freqs.into_iter() {
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for i in 0..positions.len() {
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for j in 0..positions.len() {
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if i == j {
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continue;
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}
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let p1 = positions[i];
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let p2 = positions[j];
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let d = p2 - p1;
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let a1 = p2 + d;
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if in_bounds(&input.bounds, a1) {
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antinodes.insert(a1);
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}
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let a2 = p1 - d;
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if in_bounds(&input.bounds, a2) {
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antinodes.insert(a2);
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}
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}
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}
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}
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antinodes.len()
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}
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fn part2(input: &Input) -> usize {
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0
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let mut freqs: BTreeMap<_, Vec<_>> = BTreeMap::new();
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for (pos, c) in input.antennas.iter() {
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freqs.entry(*c).or_default().push(*pos);
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}
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let mut antinodes = BTreeSet::new();
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for (_, positions) in freqs.into_iter() {
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for i in 0..positions.len() {
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for j in 0..positions.len() {
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if i == j {
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continue;
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}
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let p1 = positions[i];
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let p2 = positions[j];
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let d = p2 - p1;
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let mut p = p2;
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loop {
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if !in_bounds(&input.bounds, p) {
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break;
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}
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antinodes.insert(p);
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p += d;
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}
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let mut p = p1;
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loop {
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if !in_bounds(&input.bounds, p) {
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break;
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}
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antinodes.insert(p);
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p -= d;
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}
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}
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}
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}
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antinodes.len()
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}
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fn in_bounds(bounds: &(Range<i32>, Range<i32>), pos: Vec2) -> bool {
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bounds.0.contains(&pos[0]) && bounds.1.contains(&pos[1])
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}
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#[derive(Debug, Clone)]
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struct Input {
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values: Vec<String>,
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bounds: (Range<i32>, Range<i32>),
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antennas: BTreeMap<Vec2, char>,
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}
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impl Input {
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fn from_file(path: impl AsRef<Path>) -> io::Result<Self> {
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let input = fs::read_to_string(path)?;
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let values = input.lines().map(str::to_string).collect();
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Ok(Self { values })
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let mut width = 0;
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let mut height = 0;
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let mut antennas = BTreeMap::new();
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for (y, line) in input.lines().enumerate() {
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for (x, c) in line.trim().chars().enumerate() {
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let pos = Vector::new([x as i32, y as i32]);
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if c != '.' {
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antennas.insert(pos, c);
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}
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width = x as i32 + 1;
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height = y as i32 + 1;
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}
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}
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let bounds = (0..width, 0..height);
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Ok(Self { bounds, antennas })
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}
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}
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@@ -46,27 +147,27 @@ mod test {
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fn test_part1() {
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let input = Input::from_file("example1.txt").unwrap();
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assert_eq!(part1(&input), 0);
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assert_eq!(part1(&input), 14);
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}
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#[test]
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fn test_part1_solution() {
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let input = Input::from_file("input.txt").unwrap();
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56-
assert_eq!(part1(&input), 0);
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assert_eq!(part1(&input), 423);
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}
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59160
#[test]
60161
fn test_part2() {
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let input = Input::from_file("example1.txt").unwrap();
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63-
assert_eq!(part2(&input), 0);
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assert_eq!(part2(&input), 34);
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}
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66167
#[test]
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fn test_part2_solution() {
68169
let input = Input::from_file("input.txt").unwrap();
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70-
assert_eq!(part2(&input), 0);
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assert_eq!(part2(&input), 1287);
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}
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}

‎2024/day25/Cargo.toml‎

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@@ -3,6 +3,6 @@ name = "day25"
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version = "0.1.0"
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edition = "2021"
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# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
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# see more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
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[dependencies]

‎2024/lib/Cargo.toml‎

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[package]
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name = "lib"
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version = "0.1.0"
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edition = "2021"
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# see more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
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[dependencies]

‎2024/lib/src/lib.rs‎

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pub mod vector;

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