2024-16 (#33)

ReadMe.md

@@ -6,6 +6,8 @@
 
 | Year-Day | Task                                                                           |                                  Scala                                  |                      Rust                      |                                 Others                                 |
 |----------|:-------------------------------------------------------------------------------|:-----------------------------------------------------------------------:|:----------------------------------------------:|:----------------------------------------------------------------------:|
+| 2024-16  | [Reindeer Maze](https://adventofcode.com/2024/day/16)                          | [Scala](scala2/src/main/scala/jurisk/adventofcode/y2024/Advent16.scala) | [Rust](rust/y2024/src/bin/solution_2024_16.rs) |                                                                        |
+| 2024-15  | [Warehouse Woes](https://adventofcode.com/2024/day/15)                         | [Scala](scala2/src/main/scala/jurisk/adventofcode/y2024/Advent15.scala) | [Rust](rust/y2024/src/bin/solution_2024_15.rs) |                                                                        |
 | 2024-14  | [Restroom Redoubt](https://adventofcode.com/2024/day/14)                       | [Scala](scala2/src/main/scala/jurisk/adventofcode/y2024/Advent14.scala) | [Rust](rust/y2024/src/bin/solution_2024_14.rs) |                                                                        |
 | 2024-13  | [Claw Contraption](https://adventofcode.com/2024/day/13)                       | [Scala](scala2/src/main/scala/jurisk/adventofcode/y2024/Advent13.scala) | [Rust](rust/y2024/src/bin/solution_2024_13.rs) |                                                                        |
 | 2024-12  | [Garden Groups](https://adventofcode.com/2024/day/12)                          | [Scala](scala2/src/main/scala/jurisk/adventofcode/y2024/Advent12.scala) | [Rust](rust/y2024/src/bin/solution_2024_12.rs) |                                                                        |

rust/common/src/grid2d.rs

@@ -131,7 +131,7 @@ pub struct MatrixGrid2D<T> {
 
 impl MatrixGrid2D<char> {
     #[must_use]
-    pub fn char_field(input: &str) -> Self {
+    pub fn parse_char_field(input: &str) -> Self {
         MatrixGrid2D::<char>::parse(input, identity)
     }
 }

rust/y2024/resources/16-test-00.txt

@@ -0,0 +1,15 @@
+###############
+#.......#....E#
+#.#.###.#.###.#
+#.....#.#...#.#
+#.###.#####.#.#
+#.#.#.......#.#
+#.#.#####.###.#
+#...........#.#
+###.#.#####.#.#
+#...#.....#.#.#
+#.#.#.###.#.#.#
+#.....#...#.#.#
+#.###.#.#.#.#.#
+#S..#.....#...#
+###############

rust/y2024/resources/16-test-01.txt

@@ -0,0 +1,17 @@
+#################
+#...#...#...#..E#
+#.#.#.#.#.#.#.#.#
+#.#.#.#...#...#.#
+#.#.#.#.###.#.#.#
+#...#.#.#.....#.#
+#.#.#.#.#.#####.#
+#.#...#.#.#.....#
+#.#.#####.#.###.#
+#.#.#.......#...#
+#.#.###.#####.###
+#.#.#...#.....#.#
+#.#.#.#####.###.#
+#.#.#.........#.#
+#.#.#.#########.#
+#S#.............#
+#################

rust/y2024/src/bin/solution_2024_12.rs

@@ -12,7 +12,7 @@ type R = usize;
 type Data = MatrixGrid2D<char>;
 
 fn parse(input: &str) -> Data {
-    MatrixGrid2D::char_field(input)
+    MatrixGrid2D::parse_char_field(input)
 }
 
 fn perimeter(coords: &HashSet<Coords>) -> R {

rust/y2024/src/bin/solution_2024_15.rs

@@ -138,7 +138,7 @@ fn parse(input: &str) -> Result<Input, Error> {
 
     let directions: Vec<Direction> = b.chars().flat_map(Direction::try_from_caret).collect();
 
-    let char_field: MatrixGrid2D<char> = MatrixGrid2D::char_field(&a);
+    let char_field: MatrixGrid2D<char> = MatrixGrid2D::parse_char_field(&a);
 
     let robot = char_field
         .find_coords_by_value(&'@')

rust/y2024/src/bin/solution_2024_16.rs

@@ -0,0 +1,168 @@
+use std::collections::HashSet;
+
+use advent_of_code_common::direction::Direction;
+use advent_of_code_common::grid2d::{Coords, Grid2D, MatrixGrid2D};
+use advent_of_code_common::parsing::Error;
+use advent_of_code_common::rotation::Rotation;
+use pathfinding::prelude::{astar, astar_bag};
+
+const DATA: &str = include_str!("../../resources/16.txt");
+
+type R = i32;
+
+#[derive(Copy, Clone, Eq, PartialEq, Hash)]
+struct State {
+    position:  Coords,
+    direction: Direction,
+}
+
+impl State {
+    fn go_straight(&self) -> Self {
+        Self {
+            position:  self.position + self.direction,
+            direction: self.direction,
+        }
+    }
+
+    fn turn(&self, rotation: Rotation) -> Self {
+        Self {
+            position:  self.position,
+            direction: self.direction.rotate(rotation),
+        }
+    }
+
+    fn successors(&self, field: &MatrixGrid2D<bool>) -> Vec<(State, R)> {
+        vec![
+            (self.go_straight(), 1),
+            (self.turn(Rotation::Left90), 1000),
+            (self.turn(Rotation::Right90), 1000),
+        ]
+        .into_iter()
+        .filter(|(s, _)| field.get(s.position) == Some(&false))
+        .collect()
+    }
+
+    fn heuristic(&self, end: Coords) -> R {
+        self.position.manhattan_distance(end) as R
+    }
+}
+
+type Input = (State, MatrixGrid2D<bool>, Coords);
+
+fn parse(input: &str) -> Result<Input, Error> {
+    let char_field = MatrixGrid2D::parse_char_field(input);
+    let start = char_field
+        .find_coords_by_value(&'S')
+        .ok_or("Start not found")?;
+    let end = char_field
+        .find_coords_by_value(&'E')
+        .ok_or("End not found")?;
+    let field = char_field.map_by_values(|c| {
+        match c {
+            '#' => true,
+            'S' | 'E' | '.' => false,
+            _ => panic!("Unknown character {c} in field"),
+        }
+    });
+    Ok((
+        State {
+            position:  start,
+            direction: Direction::East,
+        },
+        field,
+        end,
+    ))
+}
+
+fn solve_1(data: &Input) -> R {
+    let (state, field, end) = data;
+    let (_, result) = astar(
+        state,
+        |s| s.successors(field),
+        |s| s.heuristic(*end),
+        |c| c.position == *end,
+    )
+    .expect("Expected a solution");
+    result
+}
+
+fn solve_2(data: &Input) -> usize {
+    let (state, field, end) = data;
+    let (results, _) = astar_bag(
+        state,
+        |s| s.successors(field),
+        |s| s.heuristic(*end),
+        |c| c.position == *end,
+    )
+    .expect("Expected a solution");
+
+    let mut visited = HashSet::new();
+    for result in results {
+        for s in result {
+            visited.insert(s.position);
+        }
+    }
+    visited.len()
+}
+
+fn main() -> Result<(), Error> {
+    let data = parse(DATA)?;
+
+    let result_1 = solve_1(&data);
+    println!("Part 1: {result_1}");
+
+    let result_2 = solve_2(&data);
+    println!("Part 2: {result_2}");
+
+    Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const TEST_DATA_0: &str = include_str!("../../resources/16-test-00.txt");
+    const TEST_DATA_1: &str = include_str!("../../resources/16-test-01.txt");
+
+    fn test_data_0() -> Input {
+        parse(TEST_DATA_0).unwrap()
+    }
+
+    fn test_data_1() -> Input {
+        parse(TEST_DATA_1).unwrap()
+    }
+
+    fn real_data() -> Input {
+        parse(DATA).unwrap()
+    }
+
+    #[test]
+    fn test_solve_1_test_0() {
+        assert_eq!(solve_1(&test_data_0()), 7036);
+    }
+
+    #[test]
+    fn test_solve_1_test_1() {
+        assert_eq!(solve_1(&test_data_1()), 11048);
+    }
+
+    #[test]
+    fn test_solve_1_real() {
+        assert_eq!(solve_1(&real_data()), 74392);
+    }
+
+    #[test]
+    fn test_solve_2_test_0() {
+        assert_eq!(solve_2(&test_data_0()), 45);
+    }
+
+    #[test]
+    fn test_solve_2_test_1() {
+        assert_eq!(solve_2(&test_data_1()), 64);
+    }
+
+    #[test]
+    fn test_solve_2_real() {
+        assert_eq!(solve_2(&real_data()), 426);
+    }
+}

scala2/src/main/resources/2024/16-test-00.txt

@@ -1 +1,15 @@
-noop
+###############
+#.......#....E#
+#.#.###.#.###.#
+#.....#.#...#.#
+#.###.#####.#.#
+#.#.#.......#.#
+#.#.#####.###.#
+#...........#.#
+###.#.#####.#.#
+#...#.....#.#.#
+#.#.#.###.#.#.#
+#.....#...#.#.#
+#.###.#.#.#.#.#
+#S..#.....#...#
+###############

scala2/src/main/resources/2024/16-test-01.txt

@@ -0,0 +1,17 @@
+#################
+#...#...#...#..E#
+#.#.#.#.#.#.#.#.#
+#.#.#.#...#...#.#
+#.#.#.#.###.#.#.#
+#...#.#.#.....#.#
+#.#.#.#.#.#####.#
+#.#...#.#.#.....#
+#.#.#####.#.###.#
+#.#.#.......#...#
+#.#.###.#####.###
+#.#.#...#.....#.#
+#.#.#.#####.###.#
+#.#.#.........#.#
+#.#.#.#########.#
+#S#.............#
+#################