Last changes

2024/Cargo.lock

@@ -220,6 +220,21 @@ dependencies = [
  "tracing-subscriber",
 ]
 
+[[package]]
+name = "day-08"
+version = "0.1.0"
+dependencies = [
+ "divan",
+ "itertools",
+ "miette",
+ "nom",
+ "rstest",
+ "test-log",
+ "thiserror 2.0.3",
+ "tracing",
+ "tracing-subscriber",
+]
+
 [[package]]
 name = "divan"
 version = "0.1.16"

2024/day-03/benches/benchmarks.rs

@@ -6,16 +6,10 @@ fn main() {
 
 #[divan::bench]
 fn part1() {
-    part1::process(divan::black_box(include_str!(
-        "../input1.txt",
-    )))
-    .unwrap();
+    part1::process(divan::black_box(include_str!("../input1.txt",))).unwrap();
 }
 
 #[divan::bench]
 fn part2() {
-    part2::process(divan::black_box(include_str!(
-        "../input2.txt",
-    )))
-    .unwrap();
+    part2::process(divan::black_box(include_str!("../input2.txt",))).unwrap();
 }

2024/day-03/src/part2.rs

@@ -1,118 +0,0 @@
-use miette::{Diagnostic, Result};
-use regex::Regex;
-use thiserror::Error;
-
-#[derive(Error, Debug, Diagnostic)]
-pub enum MultiplicationError {
-    #[error("Failed to parse first value: {0}")]
-    #[diagnostic(code(calculator::parse_error::first_value))]
-    FirstValueParseError(String),
-
-    #[error("Failed to parse second value: {0}")]
-    #[diagnostic(code(calculator::parse_error::second_value))]
-    SecondValueParseError(String),
-
-    #[error("Invalid multiplication format")]
-    #[diagnostic(code(calculator::parse_error::format))]
-    InvalidFormat,
-}
-
-#[derive(Debug)]
-struct Multiplication(usize, usize);
-
-impl Multiplication {
-    fn calculate(&self) -> usize {
-        self.0 * self.1
-    }
-}
-
-impl<T, U> TryFrom<(T, U)> for Multiplication
-where
-    T: AsRef<str>,
-    U: AsRef<str>,
-{
-    type Error = MultiplicationError;
-    fn try_from(value: (T, U)) -> std::result::Result<Self, Self::Error> {
-        let first =
-            value.0.as_ref().parse().map_err(|_| {
-                MultiplicationError::FirstValueParseError(value.0.as_ref().to_string())
-            });
-        let second =
-            value.1.as_ref().parse().map_err(|_| {
-                MultiplicationError::SecondValueParseError(value.1.as_ref().to_string())
-            });
-        Ok(Self(first?, second?))
-    }
-}
-
-#[derive(Error, Debug, Diagnostic)]
-pub enum CalculatorError {
-    #[error("Failed to compile regex: {0}")]
-    #[diagnostic(code(calculator::regex_error))]
-    RegexError(#[from] regex::Error),
-
-    #[diagnostic(code(calculator::multiplication_error))]
-    #[error("Failed to parse multiplication: {0}")]
-    MultiplicationError(#[from] MultiplicationError),
-
-    #[error("Failed to process input: {0}")]
-    #[diagnostic(code(calculator::process_error))]
-    ProcessError(String),
-}
-
-#[derive(Debug)]
-struct Calculator {
-    do_re: Regex,
-    mult_re: Regex,
-}
-
-impl Calculator {
-    fn new() -> Result<Self, CalculatorError> {
-        Ok(Self {
-            do_re: Regex::new(r"^.*?don't\(\)|do\(\)(.*?)don't\(\)|do\(\).*$")?,
-            mult_re: Regex::new(r"mul\((\d{1,3}),(\d{1,3})\)")?,
-        })
-    }
-
-    fn extract_multiplications<'a>(
-        &'a self,
-        line: &'a str,
-    ) -> impl Iterator<Item = Multiplication> + 'a {
-        self.mult_re.captures_iter(line).filter_map(|caps| {
-            Multiplication::try_from((caps.get(1)?.as_str(), caps.get(2)?.as_str())).ok()
-        })
-    }
-
-    fn extract_do<'a>(&'a self, line: &'a str) -> impl Iterator<Item = &'a str> + 'a {
-        self.do_re
-            .captures_iter(line)
-            .filter_map(|caps| caps.get(0).map(|m| m.as_str()))
-    }
-
-    fn process(&self, input: &str) -> usize {
-        let value = input.lines().collect::<String>();
-        self.extract_do(&value)
-            .flat_map(|line| self.extract_multiplications(line))
-            .map(|mult| mult.calculate())
-            .sum()
-    }
-}
-
-#[tracing::instrument]
-pub fn process(input: &str) -> Result<usize> {
-    let calculator = Calculator::new()?;
-    Ok(calculator.process(input))
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_process() -> Result<()> {
-        let input = "xmul(2,4)&mul[3,7]!^don't()_mul(5,5)+mul(32,64](mul(11,8)undo()?mul(8,5))";
-        let result = 48;
-        assert_eq!(process(input)?, result);
-        Ok(())
-    }
-}

2024/day-08/Cargo.toml

@@ -0,0 +1,28 @@
+[package]
+name = "day-08"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+itertools.workspace = true
+nom.workspace = true
+tracing.workspace = true
+tracing-subscriber.workspace = true
+miette.workspace = true
+thiserror.workspace = true
+
+[dev-dependencies]
+divan.workspace = true
+rstest.workspace = true
+test-log.workspace = true
+
+[[bench]]
+name = "day-08-bench"
+path = "benches/benchmarks.rs"
+harness = false
+
+[lints.clippy]
+pedantic = "warn"
+nursery = "warn"

2024/day-08/benches/benchmarks.rs

@@ -0,0 +1,21 @@
+use day_08::*;
+
+fn main() {
+    divan::main();
+}
+
+#[divan::bench]
+fn part1() {
+    part1::process(divan::black_box(include_str!(
+        "../input1.txt",
+    )))
+    .unwrap();
+}
+
+#[divan::bench]
+fn part2() {
+    part2::process(divan::black_box(include_str!(
+        "../input2.txt",
+    )))
+    .unwrap();
+}

2024/day-08/src/bin/part1.rs

@@ -0,0 +1,12 @@
+use day_08::part1::process;
+use miette::{Context, Result};
+
+#[tracing::instrument]
+fn main() -> Result<()> {
+    tracing_subscriber::fmt::init();
+
+    let file = include_str!("../../input1.txt");
+    let result = process(file).context("process part 1")?;
+    println!("{result}");
+    Ok(())
+}

2024/day-08/src/bin/part2.rs

@@ -0,0 +1,12 @@
+use day_08::part2::process;
+use miette::{Context, Result};
+
+#[tracing::instrument]
+fn main() -> Result<()> {
+    tracing_subscriber::fmt::init();
+
+    let file = include_str!("../../input2.txt");
+    let result = process(file).context("process part 2")?;
+    println!("{result}");
+    Ok(())
+}

2024/day-08/src/lib.rs

@@ -0,0 +1,2 @@
+pub mod part1;
+pub mod part2;

2024/day-08/src/part1.rs

@@ -0,0 +1,341 @@
+use std::{
+    collections::HashMap,
+    fmt::Display,
+    ops::{Add, Sub},
+    str::FromStr,
+};
+
+use miette::{Diagnostic, Result};
+use thiserror::Error;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+struct Vec2 {
+    row: usize,
+    col: usize,
+}
+
+impl Vec2 {
+    const fn abs_diff(self, other: Self) -> Self {
+        Self {
+            row: self.row.abs_diff(other.row),
+            col: self.col.abs_diff(other.col),
+        }
+    }
+
+    const fn manhattan_distance(self, other: Self) -> usize {
+        let diff = self.abs_diff(other);
+        diff.row + diff.col
+    }
+}
+
+impl From<Vec2> for (usize, usize) {
+    fn from(value: Vec2) -> Self {
+        (value.row, value.col)
+    }
+}
+
+impl Add for Vec2 {
+    type Output = Self;
+    fn add(self, rhs: Self) -> Self::Output {
+        Self {
+            row: self.row + rhs.row,
+            col: self.col + rhs.col,
+        }
+    }
+}
+
+impl Sub for Vec2 {
+    type Output = Self;
+    fn sub(self, rhs: Self) -> Self::Output {
+        Vec2 {
+            row: self.row.saturating_sub(rhs.row),
+            col: self.col.saturating_sub(rhs.col),
+        }
+    }
+}
+
+#[derive(Debug, PartialEq, Eq)]
+enum Location {
+    Antenna(char),
+    Antinode,
+    Empty,
+}
+
+impl From<char> for Location {
+    fn from(value: char) -> Self {
+        match value {
+            '.' => Self::Empty,
+            '#' => Self::Antinode,
+            ch => Self::Antenna(ch),
+        }
+    }
+}
+
+impl Display for Location {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let ch = match self {
+            Self::Antenna(ch) => *ch,
+            Self::Antinode => '#',
+            Self::Empty => '.',
+        };
+        write!(f, "{}", ch)
+    }
+}
+
+#[derive(Debug, Error, Diagnostic)]
+enum RoofError {
+    #[error("Failed to parse roof")]
+    ParseError,
+}
+
+fn calculate_diffs(positions: &[Vec2]) -> Vec<Vec2> {
+    positions
+        .iter()
+        .enumerate()
+        .flat_map(|(idx, &pos1)| {
+            positions[idx + 1..]
+                .iter()
+                .map(move |&pos2| pos1.abs_diff(pos2))
+        })
+        .collect()
+}
+
+#[derive(Debug, PartialEq, Eq)]
+struct Roof(Vec<Vec<Location>>);
+
+impl Roof {
+    fn place_antinodes(&mut self) {
+        let antenna_positions = self.antenna_positions();
+        for (_, pos) in antenna_positions.iter() {
+            for i in 0..pos.len() {
+                for j in (i + 1)..pos.len() {
+                    let (pos1, pos2) = (pos[i], pos[j]);
+
+                    if let Some(antinode_pos) = self.find_antinode_position(pos1, pos2) {
+                        self.0[antinode_pos.row][antinode_pos.col] = Location::Antinode;
+                    }
+                }
+            }
+        }
+    }
+
+    fn find_antinode_position(&self, pos1: Vec2, pos2: Vec2) -> Option<Vec2> {
+        let diff = pos1.abs_diff(pos2);
+        let total_dist = diff.row + diff.col;
+
+        // Try each step between the antennas
+        for step in 0..=total_dist {
+            let row = if pos1.row < pos2.row {
+                pos1.row + step.min(diff.row)
+            } else {
+                pos1.row - step.min(diff.row)
+            };
+
+            let col = if pos1.col < pos2.col {
+                pos1.col + step.min(diff.col)
+            } else {
+                pos1.col - step.min(diff.col)
+            };
+
+            let candidate = Vec2 { row, col };
+
+            // Check if position is valid and equidistant
+            if row < self.0.len()
+                && col < self.0[0].len()
+                && matches!(self.0[row][col], Location::Empty)
+            {
+                let dist1 = pos1.manhattan_distance(candidate);
+                let dist2 = pos2.manhattan_distance(candidate);
+                if dist1 == dist2 {
+                    return Some(candidate);
+                }
+            }
+        }
+        None
+    }
+
+    fn antenna_positions(&self) -> HashMap<char, Vec<Vec2>> {
+        self.0
+            .iter()
+            .enumerate()
+            .flat_map(|(row_idx, row)| {
+                row.iter()
+                    .enumerate()
+                    .filter_map(move |(col_idx, col)| match col {
+                        Location::Antenna(ch) => Some((
+                            *ch,
+                            Vec2 {
+                                row: row_idx,
+                                col: col_idx,
+                            },
+                        )),
+                        _ => None,
+                    })
+            })
+            .fold(HashMap::new(), |mut acc, (key, pos)| {
+                acc.entry(key).or_default().push(pos);
+                acc
+            })
+    }
+
+    fn count(&self) -> usize {
+        self.0
+            .iter()
+            .map(|row| {
+                row.iter()
+                    .filter(|pos| matches!(pos, Location::Antinode))
+                    .count()
+            })
+            .sum()
+    }
+
+    fn row_len(&self) -> usize {
+        self.0.len()
+    }
+
+    fn col_len(&self) -> usize {
+        self.0[0].len()
+    }
+
+    fn is_within_bounds(&self, pos: &Vec2) -> bool {
+        pos.row < self.row_len() && pos.col < self.col_len()
+    }
+}
+
+impl FromStr for Roof {
+    type Err = RoofError;
+    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
+        let roof = s
+            .lines()
+            .map(|line| line.chars().map(Location::from).collect::<Vec<_>>())
+            .collect::<Vec<_>>();
+        Ok(Self(roof))
+    }
+}
+
+impl Display for Roof {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        for (idx, row) in self.0.iter().enumerate() {
+            for pos in row {
+                write!(f, "{}", pos)?;
+            }
+            if idx < self.0.len() - 1 {
+                writeln!(f)?;
+            }
+        }
+        Ok(())
+    }
+}
+
+#[tracing::instrument]
+pub fn process(input: &str) -> Result<usize> {
+    let mut roof = Roof::from_str(input)?;
+    roof.place_antinodes();
+    println!("{roof}");
+    Ok(roof.count())
+}
+
+#[cfg(test)]
+mod tests {
+    use rstest::rstest;
+
+    use super::*;
+
+    #[test]
+    fn test_process() -> Result<()> {
+        let input = "............
+........0...
+.....0......
+.......0....
+....0.......
+......A.....
+............
+............
+........A...
+.........A..
+............
+............";
+        let result = 14;
+        assert_eq!(process(input)?, result);
+        Ok(())
+    }
+
+    #[rstest]
+    #[case(
+        "..........
+..........
+..........
+....a.....
+..........
+.....a....
+..........
+..........
+..........
+..........",
+        "..........
+...#......
+..........
+....a.....
+..........
+.....a....
+..........
+......#...
+..........
+.........."
+    )]
+    /* #[case(
+            "..........
+    ..........
+    ..........
+    ....a.....
+    ........a.
+    .....a....
+    ..........
+    ..........
+    ..........
+    ..........",
+            "..........
+    ...#......
+    #.........
+    ....a.....
+    ........a.
+    .....a....
+    ..#.......
+    ......#...
+    ..........
+    .........."
+        )]
+        #[case(
+            "............
+    ........0...
+    .....0......
+    .......0....
+    ....0.......
+    ......A.....
+    ............
+    ............
+    ........A...
+    .........A..
+    ............
+    ............",
+            "......#....#
+    ...#....0...
+    ....#0....#.
+    ..#....0....
+    ....0....#..
+    .#....A.....
+    ...#........
+    #......#....
+    ........A...
+    .........A..
+    ..........#.
+    ..........#."
+        )] */
+    fn test_layout(#[case] input_str: &str, #[case] output_str: &str) -> Result<()> {
+        let mut input = Roof::from_str(input_str)?;
+        input.place_antinodes();
+        let output = Roof::from_str(output_str)?;
+        assert_eq!(input, output);
+        Ok(())
+    }
+}

2024/day-08/src/part2.rs

@@ -0,0 +1,21 @@
+use miette::Result;
+
+#[tracing::instrument]
+pub fn process(input: &str) -> Result<usize> {
+    todo!("day xx - part 2");
+    Ok(0)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_process() -> Result<()> {
+        let input = "";
+        todo!("haven't built test yet");
+        let result = 0;
+        assert_eq!(process(input)?, result);
+        Ok(())
+    }
+}