Add day 8

Cargo.toml

@@ -6,5 +6,6 @@ edition = "2021"
 [dependencies]
 aoc-runner = "0.3.0"
 aoc-runner-derive = "0.3.0"
+itertools = "0.13.0"
 memoize = "0.4.2"
 regex = "1.11.1"

input/2024/day8.txt

@@ -0,0 +1,50 @@
+...........................A.............W........
+.......x..........AZ......P.........m......k..W...
+....v.....Z..K...V..........A.......R....f........
+.............d..........V.............2...........
+.........Z........d...V.....B....C.....e..........
+............Z.vA...........m...................s.W
+...x..o.....................ek....................
+...O.....VK..................R......B.............
+.........O..................my....kB..............
+.v...................y..........C........B.....z..
+xb.v..................................C..z........
+.........................2.ey.....................
+..K.......................y...................s...
+..........................................z.......
+.......................2.......R........z......F..
+O.....d..................D..k.........F...........
+..........O..........D.............s....E.........
+..o......9....................D........C..s.......
+.....o..r....................c...................m
+.......P..............................e...........
+..............1......................d............
+...................o...............3..............
+........................c.......24..........S.....
+....x..................c.............F4.........S.
+P............N..8.......W.D.......................
+.....K............1.8.............................
+.........P..............Q...M.....................
+9...................R........4...8.....0..........
+....n.........................F...................
+........Y...n......1......................3..J....
+.........................3...8....................
+...n...M............................0.......ja...S
+....f................................6.....S.....E
+....................i.........M...J...............
+...r..........q..........1......l..0.....L........
+.........f7....i.Nc......................j.......l
+..9....Y7......X.........Q...M5....J4...........3.
+.Y........NX..I............Q........L.............
+......Xw...nb.............0..............l6.......
+......b.....f....5..q.....................a..6....
+.......5..........iq.9.....p..........a...........
+........X........I................p...6...........
+..................N.............L.........j.......
+...b.7.......................p....Q......E........
+....Y....7......................p................j
+.......r..........................................
+.................i...................a............
+..w.........5.....................................
+......w........I..............J...................
+.w............r.....................lL............

src/day12.rs

@@ -0,0 +1,10 @@
+// use aoc_runner_derive::{aoc, aoc_generator};
+
+// #[aoc_generator(day8)]
+// pub fn input_generator(input: &str) -> (Vec<usize>, Vec<usize>) {
+
+// #[aoc(day8, part1)]
+// pub fn part1(input: &[Equation]) -> usize {
+
+// #[aoc(day8, part2)]
+// pub fn part2(input: &[Equation]) -> usize {

src/day8.rs

@@ -1,10 +1,142 @@
-// use aoc_runner_derive::{aoc, aoc_generator};
+use aoc_runner_derive::{aoc, aoc_generator};
+use std::collections::{HashMap, HashSet};
 
-// #[aoc_generator(day8)]
-// pub fn input_generator(input: &str) -> (Vec<usize>, Vec<usize>) {
+#[derive(Debug)]
+pub struct City {
+    frequencies: HashMap<char, HashSet<(usize, usize)>>,
+    y_len: usize,
+    x_len: usize,
+}
 
-// #[aoc(day8, part1)]
-// pub fn part1(input: &[Equation]) -> usize {
+#[aoc_generator(day8)]
+pub fn input_generator(input: &str) -> City {
+    let mut frequencies: HashMap<char, HashSet<(usize, usize)>> = HashMap::new();
+    let map: Vec<Vec<char>> = input
+        .lines()
+        .enumerate()
+        .map(|(y, l)| {
+            l.chars()
+                .enumerate()
+                .map(|(x, c)| {
+                    if c != '.' {
+                        frequencies.entry(c).or_default().insert((y, x));
+                    }
+                    c
+                })
+                .collect()
+        })
+        .collect();
+    City {
+        y_len: map.len(),
+        x_len: map[0].len(),
+        frequencies,
+    }
+}
 
-// #[aoc(day8, part2)]
-// pub fn part2(input: &[Equation]) -> usize {
+#[aoc(day8, part1)]
+pub fn part1(input: &City) -> usize {
+    let mut antinodes: HashSet<(usize, usize)> = HashSet::new();
+    let mut count = 0;
+    for positions in input.frequencies.values() {
+        for current_pos in positions {
+            for around_pos in positions {
+                if current_pos == around_pos {
+                    continue;
+                }
+                let y = (current_pos.0 * 2).wrapping_sub(around_pos.0);
+                let x = (current_pos.1 * 2).wrapping_sub(around_pos.1);
+                if y < input.y_len && x < input.x_len && !antinodes.contains(&(y, x)) {
+                    count += 1;
+                    antinodes.insert((y, x));
+                }
+            }
+        }
+    }
+    count
+}
+
+#[aoc(day8, part2)]
+pub fn part2(input: &City) -> usize {
+    let mut antinodes: HashSet<(usize, usize)> = HashSet::new();
+    let mut count = 0;
+    for positions in input.frequencies.values() {
+        for current_pos in positions {
+            for around_pos in positions {
+                if current_pos == around_pos {
+                    continue;
+                }
+                let delta_y: isize = current_pos.0 as isize - around_pos.0 as isize;
+                let delta_x: isize = current_pos.1 as isize - around_pos.1 as isize;
+
+                let mut y: isize = around_pos.0 as isize;
+                let mut x: isize = around_pos.1 as isize;
+                loop {
+                    y -= delta_y;
+                    x -= delta_x;
+                    if x < 0 || y < 0 || x >= input.x_len as isize || y >= input.y_len as isize {
+                        break;
+                    }
+                    if !antinodes.contains(&(y as usize, x as usize)) {
+                        count += 1;
+                        antinodes.insert((y as usize, x as usize));
+                    }
+                }
+
+                y = around_pos.0 as isize;
+                x = around_pos.1 as isize;
+                loop {
+                    y = y.wrapping_add(delta_y);
+                    x = x.wrapping_add(delta_x);
+                    if x < 0 || y < 0 || x >= input.x_len as isize || y >= input.y_len as isize {
+                        break;
+                    }
+                    if !antinodes.contains(&(y as usize, x as usize)) {
+                        count += 1;
+                        antinodes.insert((y as usize, x as usize));
+                    }
+                }
+            }
+        }
+    }
+
+    count
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const INPUT: &str = "............
+........0...
+.....0......
+.......0....
+....0.......
+......A.....
+............
+............
+........A...
+.........A..
+............
+............
+";
+    //     const INPUT: &str = "T.........
+    // ...T......
+    // .T........
+    // ..........
+    // ..........
+    // ..........
+    // ..........
+    // ..........
+    // ..........
+    // ..........";
+
+    #[test]
+    fn test_part1() {
+        assert_eq!(14, part1(&input_generator(INPUT)))
+    }
+
+    #[test]
+    fn test_part2() {
+        assert_eq!(34, part2(&input_generator(INPUT)))
+    }
+}

src/day9.rs

@@ -0,0 +1,10 @@
+// use aoc_runner_derive::{aoc, aoc_generator};
+
+// #[aoc_generator(day8)]
+// pub fn input_generator(input: &str) -> (Vec<usize>, Vec<usize>) {
+
+// #[aoc(day8, part1)]
+// pub fn part1(input: &[Equation]) -> usize {
+
+// #[aoc(day8, part2)]
+// pub fn part2(input: &[Equation]) -> usize {

src/lib.rs

@@ -9,5 +9,6 @@ mod day4;
 mod day5;
 mod day6;
 mod day7;
+mod day8;
 
 aoc_lib! { year = 2024 }