Day 11

day11/Cargo.lock

@@ -0,0 +1,16 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "anyhow"
+version = "1.0.77"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c9d19de80eff169429ac1e9f48fffb163916b448a44e8e046186232046d9e1f9"
+
+[[package]]
+name = "day11"
+version = "0.1.0"
+dependencies = [
+ "anyhow",
+]

day11/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "day11"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+anyhow = "1.0.77"

day11/input

@@ -0,0 +1,140 @@
+.............................................................................................#..............................................
+...#....................#............................#......................#........................#...........#................#.........
+................#.....................................................#..............#.....................#................................
+................................................................#.......................................................#...................
+.......#........................#.........................#..............................#.....#............................................
+............#............................#..................................................................................................
+......................#........................#......................................................#.....................................
+....................................#.....................................#.................#..........................................#....
+................................................................................................................#..............#............
+...................#.................................................#............................#.........................................
+............................................#.........#...............................#.................#...................................
+.....#.....................#..................................................#.............................................................
+........................................................................#.................#.................................................
+...............................................................#.....................................................#............#.........
+..............#.......................#...........................................#.........................................................
+.......................#.......................#...........................................................#................................
+.........#........................................................#.........................................................................
+.........................................................................#................................................................#.
+............................#..........................#........................#.....#...............................#.....................
+.....................................#..................................................................#....................#..............
+#...........................................................................................................................................
+..........#......................#...........#............#............#....................................................................
+....................#.........................................................#.................................#...........................
+.................................................#.............#.....................#..........#......................#..........#.........
+....................................#.......................................................................................................
+..........................................#..............................................................................................#..
+......................#.....................................................................................#.....#.........#...............
+...........#................#.............................#.............#.....................#.............................................
+#.................#...............................................#...........#.............................................................
+.......................................#.................................................#..................................................
+.....#.......................................#.......................................................#..............................#......#
+..............#.................#.................#..................#..............#..............................#........................
+...........................................................................#................................................................
+.........................#............................#....................................................#................#...............
+.#..............................................................................#...........................................................
+.......................................#................................#......................#............................................
+................#...........#...................#.......................................................................................#...
+..............................................................#..........................................................#..................
+.......#......................................................................#.........#.............#.....................................
+.......................................................#....................................................................................
+......................#................................................#....................................#.............................#.
+#.........................................#......................................................................#..........................
+..................................#................#............................................#.......#...................................
+.....#.....................#.............................#.............................#....................................................
+................#...............................................#...........................................................................
+...............................#................................................#....................#..........................#...........
+......................................................#....................#................#................#..............................
+..#..........................................#......................................................................#.......................
+.............#..............................................................................................................................
+.......................................................................................................................................#....
+.......................#..............#...........................#............................#...............#............................
+.........#..................#...............................................#...........#...................................................
+......................................................................#........................................................#............
+..............................................................#....................#...............#......#........#........................
+..............#...................#.............#.....................................................................................#.....
+............................................................................................................................................
+.....................#.....#............#...........#......................................#................................................
+..........#...................................................................................................................#...........#.
+...#......................................................................#.....................#................#..........................
+.............................................#...........................................................................#..................
+......................................................#...........#................#................#.................................#.....
+.................................#.....................................#..................#...............#......................#..........
+............................................................................................................................................
+.......#..............................................................................................................#.....................
+.....................#..............#......#.................................................#..............................................
+..............................#..................................#..............#............................#..............................
+..........#...............................................#............................#..........................................#.........
+#.................................................#...................#...........................#.........................................
+.......................................#....................................................................................................
+.......#...........................................................................#........................................................
+................#............................................#............................................#.........#....................#..
+.......................#........#.........#...............................................................................#.................
+............................................................................................................................................
+..#................#........................................................................................................................
+..........#...........................................#......................................#..............................................
+............................................................................................................................................
+.....#.....................................#...................#....................................................................#.......
+.........................#...........#............#.................................................................#....................#..
+........................................................#...............#...................................................................
+............#.................#.................................................#......#..............#.....................................
+.............................................................................................#................#................#............
+........................................#.......................#..........................................................................#
+..#.................#..........................#......................#.............#..............#...................#.............#......
+............................#............................#................................#......................#..........................
+.............#.................................................................................#............................................
+.................................#.........................................#................................................................
+.........................#.........................#.................................................#........................#.............
+.......#......................................................#.............................................................................
+............................................................................................................................................
+............................................................................................................................................
+.......................#.........................................................................................#..........................
+...#...........................#..................................................................#......#................#.................
+...............................................#................#...........................................................................
+....................#.................................#.................#.......#..........#........................................#.......
+...........#.................................................................................................#.............................#
+.#..................................................................................................#.......................................
+.....................................#.................................................................................#....................
+...............#.........#...........................................................#......................................................
+................................#........................#........#.........................................................................
+......#..........................................#.............................................................................#............
+...............................................................................................#.......#....................................
+...............................................................................................................#............................
+..............................#...........#............................#.................................................#............#.....
+...................#...........................#............................................................................................
+...............................................................#.....................#.....#................................................
+........#.................#.......................................................................................#...........#.............
+...............#............................#.........#.......................#...........................#.................................
+.#...................................#...................................#................................................................#.
+.........................................................................................#...........................................#......
+........................#...................................................................................................................
+....................................................................................................................#.......................
+........................................#.....#.........#.........#.........................................................................
+.......................................................................................#............#.......................................
+.#..............................#.............................................................#........................#.....#.....#........
+............#...............................................................#.................................#.........................#...
+..............................................................#.........................................#...................................
+........................#..............................#...............#........#.........#.................................................
+...................#........................#.......................................................................#.......................
+.......................................#...................................................................#................................
+..............#..................#..............#...................................................................................#.......
+........#......................................................#..............#.................#.........................................#.
+....................................................................#.......................................................#...............
+.............................#..........................................................................#...................................
+.................#..................................................................#.......................................................
+............................................#..........................#............................................#..............#........
+......#..............#..........................................#...........#..............................#................................
+............#.....................#.................................................................#.......................................
+...........................#.............#...............#..................................................................#...............
+#....................................................................................................................................#......
+.............................................................#.....................#........................................................
+.......#..........................................#.................#....................................#........#.......................#.
+..........................................................................................#.................................................
+..........................#..............................................#......................#...........................................
+...............................#.....................#..........................#.............................#.............................
+....#......#................................................#..........................#.......................................#............
+..................#.............................#...........................................................................................
+...........................................#..................................................#.............................................
+.......................#...........................................#...................................................#...................#
+.......#......#.............#.........................#..................#..............................#...........................#.......
+..#..............................................................................................................#..........................

day11/src/main.rs

@@ -0,0 +1,71 @@
+use std::io::stdin;
+
+use anyhow::Result;
+
+#[derive(Debug)]
+struct Space {
+    galaxies: Vec<(usize, usize)>,
+}
+
+fn main() -> Result<()> {
+    let space = Space::load()?;
+    let total: usize = space.pairs()
+        .map(|(a,b)| manhattan_distance(a,b))
+        .sum();
+    println!("Part 1: total distance {total}");
+    Ok(())
+}
+
+fn manhattan_distance(a: (usize,usize), b: (usize,usize)) -> usize {
+    a.0.abs_diff(b.0) + a.1.abs_diff(b.1)
+}
+
+const EXPANSION_FACTOR: usize = 1_000_000 - 1;
+
+impl Space {
+
+    fn load() -> Result<Space> {
+        let mut galaxies = vec![];
+
+        let mut empty_lines = vec![];
+        let mut non_empty_columns = vec![];
+
+        for (x, l) in
+            stdin().lines().enumerate()
+        {
+            let mut empty = true;
+            for (y,c) in l?.chars().enumerate() {
+                if c == '#' {
+                    empty = false;
+                    galaxies.push((x,y));
+                    if non_empty_columns.len() <= y {
+                        non_empty_columns.resize(y+1, false);
+                    }
+                    non_empty_columns[y] = true;
+                }
+            }
+            if empty { empty_lines.push(x) };
+        }
+
+        let empty_columns: Vec<_> = non_empty_columns.iter()
+            .enumerate()
+            .filter_map(|(y, full)| Some(y).filter(|_| !full))
+            .collect();
+            
+        for (x,y) in &mut galaxies {
+            *x += EXPANSION_FACTOR * empty_lines.iter().filter(|&&l| l < *x).count();
+            *y += EXPANSION_FACTOR * empty_columns.iter().filter(|&&c| c < *y).count();
+        }
+
+        Ok(Space { galaxies })
+    }
+
+    fn pairs(&self) -> impl Iterator<Item=((usize,usize),(usize,usize))> + '_ {
+        self.galaxies.iter()
+            .enumerate()
+            .flat_map(|(i, &a)| {
+                self.galaxies.iter().skip(i+1).map(move |&b| { (a,b)})
+            })
+    }
+
+}

day11/test

@@ -0,0 +1,10 @@
+...#......
+.......#..
+#.........
+..........
+......#...
+.#........
+.........#
+..........
+.......#..
+#...#.....