From: alex <>
Date: Wed, 25 Dec 2024 15:24:14 +0000 (+0100)
Subject: Day25 - part 1
X-Git-Url: https://aoc.elinar.fr/?a=commitdiff_plain;ds=sidebyside;p=aoc_2024

Day25 - part 1
---

diff --git a/src/day25.rs b/src/day25.rs
new file mode 100644
index 0000000..d548139
--- /dev/null
+++ b/src/day25.rs
@@ -0,0 +1,143 @@
+use std::error::Error;
+use std::path::Path;
+use std::collections::HashMap;
+
+const WIDTH: u8 = 5;
+const HEIGHT: u8 = 7;
+
+struct Puzzle {
+    locks: Vec<Vec<u8>>,
+    keys: Vec<Vec<u8>>,
+}
+
+impl Puzzle {
+    pub fn new(input: &str) -> Self {
+        let mut locks: Vec<Vec<u8>> = Vec::new();
+        let mut keys: Vec<Vec<u8>> = Vec::new();
+
+        input.split("\n\n").for_each(|b| {
+            let mut block: HashMap<(u8, u8), u8> = HashMap::new();
+            b.lines().enumerate()
+                .for_each(|(row, line)| {
+                    line.as_bytes().iter().enumerate()
+                        .for_each(|(col, value)| {
+                            block.insert((row as u8, col as u8), *value);
+                        });
+                });
+
+            let mut heights: Vec<u8> = Vec::new();
+            (0..WIDTH).for_each(|i| {
+                heights.push(
+                    block.iter().filter(|&((_, col), value)| {
+                        *col == i && *value == b'#'
+                    })
+                    .count() as u8 - 1 // remove the base row
+                );
+            });
+
+            match *block.get(&(0,0)).unwrap() {
+                b'#' => locks.push(heights),
+                b'.' => keys.push(heights),
+                _ => unreachable!(),
+            }
+
+        });
+
+        Self { locks, keys }
+    }
+
+    fn unique_key_lock_pairs(&self) -> u32 {
+        let mut count: u32 = 0;
+        self.locks.iter().for_each(|lock| {
+            count += self.keys.iter().filter(|key| {
+                key.iter().zip(lock.iter()).all(|(k, l)| k + l + 1 < HEIGHT)
+            })
+            .count() as u32;
+        });
+        count
+    }
+}
+
+fn run_part1(input: &str) -> Result<u32, Box<dyn Error>> {
+    println!("Running {} - part 1", get_day());
+
+    let puzzle = Puzzle::new(input);
+    Ok(puzzle.unique_key_lock_pairs())
+}
+
+fn run_part2(input: &str) -> Result<u32, Box<dyn Error>> {
+    println!("Running {} - part 2", get_day());
+
+    Ok(0)
+}
+
+pub fn run(input: &str) -> Result<(), Box<dyn Error>> {
+    let res = run_part1(input)?;
+    println!("{res}");
+
+    let res = run_part2(input)?;
+    println!("{res}");
+
+    Ok(())
+}
+
+fn get_day() -> String {
+    let filename = file!();
+    Path::new(filename).file_stem().unwrap().to_str().unwrap().to_string()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    static TEXT_INPUT: &str = "\
+#####
+.####
+.####
+.####
+.#.#.
+.#...
+.....
+
+#####
+##.##
+.#.##
+...##
+...#.
+...#.
+.....
+
+.....
+#....
+#....
+#...#
+#.#.#
+#.###
+#####
+
+.....
+.....
+#.#..
+###..
+###.#
+###.#
+#####
+
+.....
+.....
+.....
+#....
+#.#..
+#.#.#
+#####";
+
+    #[test]
+    fn test_part1() {
+        assert_eq!(3, run_part1(TEXT_INPUT).unwrap());
+    }
+
+    #[test]
+    fn test_part2() {
+        assert_eq!(0, run_part2(TEXT_INPUT).unwrap());
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index a7f650f..f4a8007 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -27,6 +27,7 @@ pub mod day20;
 pub mod day22;
 pub mod day23;
 pub mod day24;
+pub mod day25;
 
 fn main() {
     let args: Vec<String> = env::args().collect();
@@ -72,6 +73,7 @@ fn run(day: &str, input_file: &str) -> Result<(), Box<dyn Error>> {
         "day22" => day22::run(&input)?,
         "day23" => day23::run(&input)?,
         "day24" => day24::run(&input)?,
+        "day25" => day25::run(&input)?,
         _ => return Err(format!("unknown or unimplemented day \"{day}\"").into()),
     }
     Ok(())