Add day14

day14/Cargo.lock

@@ -0,0 +1,61 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "aho-corasick"
+version = "1.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e60d3430d3a69478ad0993f19238d2df97c507009a52b3c10addcd7f6bcb916"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "day14"
+version = "0.1.0"
+dependencies = [
+ "glam",
+ "regex",
+]
+
+[[package]]
+name = "glam"
+version = "0.29.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc46dd3ec48fdd8e693a98d2b8bafae273a2d54c1de02a2a7e3d57d501f39677"
+
+[[package]]
+name = "memchr"
+version = "2.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "78ca9ab1a0babb1e7d5695e3530886289c18cf2f87ec19a575a0abdce112e3a3"
+
+[[package]]
+name = "regex"
+version = "1.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b544ef1b4eac5dc2db33ea63606ae9ffcfac26c1416a2806ae0bf5f56b201191"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.4.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "809e8dc61f6de73b46c85f4c96486310fe304c434cfa43669d7b40f711150908"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.8.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2b15c43186be67a4fd63bee50d0303afffcef381492ebe2c5d87f324e1b8815c"

day14/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "day14"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+glam = "0.29.2"
+regex = "1.11.1"

day14/src/main.rs

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+use glam::IVec2;
+use regex::Regex;
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+struct Robot {
+    position: IVec2,
+    velocity: IVec2,
+}
+
+#[rustfmt::skip]
+fn parse(input: &str) -> Vec<Robot> {
+    let re = Regex::new(r"-?\d+").unwrap();
+    input.lines().map(|l| {
+        let mut captures = re.captures_iter(l);
+        Robot {
+            position: IVec2 {
+                x: captures.next().unwrap().get(0).unwrap().as_str().parse().unwrap(),
+                y: captures.next().unwrap().get(0).unwrap().as_str().parse().unwrap(),
+            },
+            velocity: IVec2 {
+                x: captures.next().unwrap().get(0).unwrap().as_str().parse().unwrap(),
+                y: captures.next().unwrap().get(0).unwrap().as_str().parse().unwrap(),
+            }
+        }
+    }).collect()
+}
+
+fn get_pos_after_steps(robot: &Robot, steps: &i32, dimensions: &IVec2) -> IVec2 {
+    let p = robot.position + steps * robot.velocity;
+    let mut res = IVec2::new(0, 0);
+    if p.x >= 0 {
+        res.x = p.x % dimensions.x;
+    } else {
+        let diff = p.x.abs() % dimensions.x;
+        if diff == 0 {
+            res.x = 0;
+        } else {
+            res.x = dimensions.x - diff;
+        }
+    }
+    if p.y >= 0 {
+        res.y = p.y % dimensions.y;
+    } else {
+        let diff = p.y.abs() % dimensions.y;
+        if diff == 0 {
+            res.y = 0;
+        } else {
+            res.y = dimensions.y - diff;
+        }
+    }
+    res
+}
+
+fn part1(input: &[Robot], dimensions: &IVec2) -> usize {
+    input
+        .iter()
+        .fold([0, 0, 0, 0], |mut acc, curr| {
+            let p = get_pos_after_steps(curr, &100, dimensions);
+            if p.x < (dimensions.x / 2) && p.y < (dimensions.y / 2) {
+                acc[0] += 1;
+            }
+            if p.x > (dimensions.x / 2) && p.y < (dimensions.y / 2) {
+                acc[1] += 1;
+            }
+            if p.x < (dimensions.x / 2) && p.y > (dimensions.y / 2) {
+                acc[2] += 1
+            }
+            if p.x > (dimensions.x / 2) && p.y > (dimensions.y / 2) {
+                acc[3] += 1;
+            }
+            acc
+        })
+        .iter()
+        .product()
+}
+
+// fn print_map(robots: &[Robot], dimensions: &IVec2) -> String {
+//     let mut res = String::new();
+//     for y in 0..dimensions.x {
+//         for x in 0..dimensions.y {
+//             if robots
+//                 .iter()
+//                 .map(|r| (r.position.x, r.position.y))
+//                 .any(|p| p == (x, y))
+//             {
+//                 res.push('#');
+//             } else {
+//                 res.push(' ');
+//             }
+//         }
+//         res.push('\n');
+//     }
+//     res
+// }
+
+fn has_tree(robots: &[Robot]) -> bool {
+    let check: Vec<_> = (0..8).map(|i| IVec2::new(i, 0)).collect();
+    robots.iter().any(|p| {
+        check
+            .iter()
+            .all(|c| robots.iter().any(|p2| p2.position == p.position + c))
+    })
+}
+
+fn part2(robots: &mut [Robot], dimensions: &IVec2) -> i32 {
+    for i in 0.. {
+        if has_tree(robots) {
+            return i;
+        }
+        robots
+            .iter_mut()
+            .for_each(|r| r.position = get_pos_after_steps(r, &1, dimensions))
+    }
+    unreachable!()
+}
+
+fn main() {
+    let mut input = parse(include_str!("../input.txt"));
+    println!("{}", part1(&input, &IVec2::new(101, 103)));
+    println!("{}", part2(&mut input, &IVec2::new(101, 103)));
+}