do day 14

2022/src/day_14.rs

@@ -0,0 +1,118 @@
+use State::*;
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+enum State {
+    Air,
+    Rock,
+    Sand,
+}
+type Coord = (i32, i32);
+type Data = Vec<Vec<Coord>>;
+type Output = i32;
+fn parse(input: &str) -> Data {
+    input
+        .lines()
+        .map(|line| {
+            line.split(" -> ")
+                .map(|coord| {
+                    let (x, y) = coord.split_once(',').unwrap();
+                    (x.parse().unwrap(), y.parse().unwrap())
+                })
+                .collect()
+        })
+        .collect()
+}
+fn part_one(data: Data) -> Output {
+    let sim_height = 300;
+    let sim_width = 1000;
+    let mut sim = vec![vec![Air; sim_height]; sim_width];
+    for line in data {
+        for w in line.windows(2) {
+            let (x1, y1) = w[0];
+            let (x2, y2) = w[1];
+            if x1 == x2 {
+                for y in std::cmp::min(y1, y2)..=std::cmp::max(y1, y2) {
+                    sim[x1 as usize][y as usize] = Rock;
+                }
+            } else if y1 == y2 {
+                for x in std::cmp::min(x1, x2)..=std::cmp::max(x1, x2) {
+                    sim[x as usize][y1 as usize] = Rock;
+                }
+            }
+        }
+    }
+    let spawn = (500, 0);
+    for i in 1.. {
+        let (mut x, mut y) = spawn;
+        loop {
+            if y + 1 >= sim_height {
+                return i - 1;
+            }
+            if sim[x][y + 1] == Air {
+                y += 1;
+            } else if sim[x - 1][y + 1] == Air {
+                x -= 1;
+                y += 1;
+            } else if sim[x + 1][y + 1] == Air {
+                x += 1;
+                y += 1;
+            } else {
+                sim[x][y] = Sand;
+                break;
+            }
+        }
+    }
+    unreachable!()
+}
+fn part_two(mut data: Data) -> Output {
+    let sim_height = 300;
+    let sim_width = 1000;
+    let mut sim = vec![vec![Air; sim_height]; sim_width];
+    let max_y = data.iter().flatten().map(|c| c.1).max().unwrap();
+    data.push(vec![(0, max_y + 2), (sim_width as i32 - 1, max_y + 2)]);
+    for line in data {
+        for w in line.windows(2) {
+            let (x1, y1) = w[0];
+            let (x2, y2) = w[1];
+            if x1 == x2 {
+                for y in std::cmp::min(y1, y2)..=std::cmp::max(y1, y2) {
+                    sim[x1 as usize][y as usize] = Rock;
+                }
+            } else if y1 == y2 {
+                for x in std::cmp::min(x1, x2)..=std::cmp::max(x1, x2) {
+                    sim[x as usize][y1 as usize] = Rock;
+                }
+            }
+        }
+    }
+    let spawn = (500, 0);
+    for i in 1.. {
+        let (mut x, mut y) = spawn;
+        loop {
+            if sim[x][y + 1] == Air {
+                y += 1;
+            } else if sim[x - 1][y + 1] == Air {
+                x -= 1;
+                y += 1;
+            } else if sim[x + 1][y + 1] == Air {
+                x += 1;
+                y += 1;
+            } else {
+                if (x, y) == spawn {
+                    return i;
+                }
+                sim[x][y] = Sand;
+                break;
+            }
+        }
+    }
+    unreachable!()
+}
+
+advent_of_code_macro::generate_tests!(
+    day 14,
+    parse,
+    part_one,
+    part_two,
+    sample tests [24, 93],
+    star tests [674, 24_958]
+);

2022/src/lib.rs

@@ -12,3 +12,4 @@ mod day_10;
 mod day_11;
 mod day_12;
 mod day_13;
+mod day_14;