Solve day 5

src/bin/05.rs

@@ -0,0 +1,92 @@
+use std::collections::VecDeque;
+
+use aoc2022::*;
+use itertools::Itertools;
+use regex::Regex;
+
+const INPUT: &str = include_str!("../../input/05");
+
+fn main() {
+    let mut game = input();
+    game.apply_actions9000();
+    solved_level_1(game.top_letters());
+
+    let mut game = input();
+    game.apply_actions9001();
+    solved_level_2(game.top_letters());
+}
+
+struct Game {
+    stacks: Vec<VecDeque<char>>,
+    actions: Vec<Action>,
+}
+
+impl Game {
+    fn top_letters(&self) -> String {
+        self.stacks
+            .iter()
+            .map(|s| s.iter().last().unwrap())
+            .collect()
+    }
+
+    fn apply_actions9000(&mut self) {
+        for a in &self.actions {
+            for _ in 0..a.count {
+                let item = self.stacks[a.from].pop_back().unwrap();
+                self.stacks[a.to].push_back(item);
+            }
+        }
+    }
+
+    fn apply_actions9001(&mut self) {
+        for a in &self.actions {
+            let drain_start = self.stacks[a.from].len() - a.count;
+            let items = self.stacks[a.from].drain(drain_start..).collect_vec();
+            self.stacks[a.to].extend(items.iter());
+        }
+    }
+}
+
+struct Action {
+    from: usize,
+    to: usize,
+    count: usize,
+}
+
+fn input() -> Game {
+    let mut stacks = Vec::new();
+    let mut actions = Vec::new();
+    let action_pattern = Regex::new(r"move (\d+) from (\d+) to (\d+)").unwrap();
+
+    for line in INPUT.lines() {
+        if line.contains('[') {
+            for (i, mut letter) in line.chars().chunks(4).into_iter().enumerate() {
+                let letter = letter.nth(1).unwrap();
+
+                if i >= stacks.len() {
+                    stacks.push(VecDeque::new());
+                }
+
+                if letter.is_whitespace() {
+                    continue;
+                }
+
+                stacks[i].push_front(letter);
+            }
+        }
+
+        if let Some(cap) = action_pattern.captures(line) {
+            let count = cap.get(1).unwrap().as_str().parse().unwrap();
+            let from: usize = cap.get(2).unwrap().as_str().parse().unwrap();
+            let to: usize = cap.get(3).unwrap().as_str().parse().unwrap();
+
+            actions.push(Action {
+                count,
+                to: to - 1,
+                from: from - 1,
+            })
+        }
+    }
+
+    Game { stacks, actions }
+}