Finish day 5

2022/data/day5.txt

@@ -0,0 +1,511 @@
+    [G]         [P]         [M]    
+    [V]     [M] [W] [S]     [Q]    
+    [N]     [N] [G] [H]     [T] [F]
+    [J]     [W] [V] [Q] [W] [F] [P]
+[C] [H]     [T] [T] [G] [B] [Z] [B]
+[S] [W] [S] [L] [F] [B] [P] [C] [H]
+[G] [M] [Q] [S] [Z] [T] [J] [D] [S]
+[B] [T] [M] [B] [J] [C] [T] [G] [N]
+ 1   2   3   4   5   6   7   8   9 
+
+move 2 from 4 to 2
+move 6 from 9 to 7
+move 4 from 7 to 2
+move 2 from 4 to 1
+move 2 from 6 to 7
+move 1 from 3 to 8
+move 4 from 7 to 1
+move 2 from 3 to 2
+move 3 from 8 to 5
+move 3 from 1 to 4
+move 12 from 2 to 5
+move 2 from 6 to 8
+move 12 from 5 to 8
+move 3 from 7 to 9
+move 18 from 8 to 9
+move 2 from 8 to 6
+move 3 from 2 to 3
+move 14 from 9 to 4
+move 1 from 1 to 3
+move 7 from 9 to 3
+move 1 from 2 to 1
+move 8 from 4 to 5
+move 5 from 6 to 3
+move 2 from 7 to 9
+move 3 from 4 to 9
+move 4 from 9 to 6
+move 4 from 6 to 1
+move 8 from 4 to 6
+move 10 from 1 to 2
+move 13 from 3 to 2
+move 17 from 5 to 9
+move 2 from 5 to 1
+move 9 from 9 to 7
+move 1 from 3 to 6
+move 2 from 1 to 8
+move 11 from 2 to 4
+move 5 from 6 to 8
+move 1 from 6 to 3
+move 1 from 1 to 4
+move 3 from 8 to 6
+move 3 from 2 to 8
+move 9 from 7 to 9
+move 4 from 4 to 7
+move 1 from 9 to 5
+move 15 from 9 to 7
+move 7 from 8 to 3
+move 1 from 5 to 6
+move 2 from 6 to 9
+move 8 from 2 to 6
+move 3 from 4 to 3
+move 1 from 2 to 5
+move 4 from 9 to 3
+move 1 from 3 to 4
+move 13 from 6 to 2
+move 1 from 5 to 1
+move 4 from 4 to 9
+move 6 from 3 to 2
+move 11 from 2 to 7
+move 6 from 3 to 4
+move 3 from 3 to 2
+move 1 from 3 to 4
+move 1 from 1 to 3
+move 3 from 9 to 2
+move 1 from 3 to 1
+move 4 from 7 to 1
+move 1 from 9 to 5
+move 5 from 1 to 4
+move 11 from 2 to 4
+move 1 from 5 to 3
+move 1 from 2 to 3
+move 12 from 4 to 2
+move 2 from 7 to 2
+move 7 from 4 to 3
+move 5 from 4 to 1
+move 7 from 7 to 6
+move 4 from 1 to 8
+move 1 from 8 to 5
+move 8 from 3 to 2
+move 4 from 7 to 4
+move 13 from 7 to 1
+move 2 from 8 to 6
+move 5 from 4 to 9
+move 1 from 3 to 6
+move 1 from 5 to 8
+move 1 from 2 to 9
+move 4 from 2 to 6
+move 2 from 8 to 6
+move 10 from 1 to 3
+move 4 from 9 to 4
+move 2 from 1 to 3
+move 5 from 2 to 9
+move 4 from 9 to 2
+move 1 from 1 to 2
+move 13 from 2 to 4
+move 15 from 4 to 5
+move 3 from 6 to 8
+move 8 from 3 to 8
+move 1 from 4 to 2
+move 14 from 5 to 1
+move 1 from 5 to 4
+move 1 from 4 to 2
+move 8 from 6 to 7
+move 3 from 6 to 2
+move 2 from 9 to 1
+move 8 from 8 to 7
+move 9 from 1 to 5
+move 7 from 5 to 3
+move 14 from 7 to 9
+move 2 from 2 to 3
+move 7 from 2 to 1
+move 1 from 6 to 1
+move 4 from 9 to 2
+move 8 from 3 to 6
+move 2 from 4 to 3
+move 4 from 3 to 5
+move 5 from 5 to 7
+move 2 from 6 to 9
+move 6 from 6 to 2
+move 4 from 2 to 3
+move 1 from 6 to 2
+move 2 from 7 to 8
+move 13 from 9 to 5
+move 2 from 7 to 1
+move 14 from 1 to 5
+move 15 from 5 to 7
+move 3 from 8 to 7
+move 5 from 3 to 5
+move 6 from 5 to 7
+move 4 from 1 to 7
+move 1 from 2 to 5
+move 3 from 2 to 8
+move 11 from 5 to 2
+move 10 from 7 to 1
+move 1 from 3 to 4
+move 10 from 2 to 9
+move 1 from 5 to 8
+move 6 from 7 to 3
+move 1 from 4 to 6
+move 2 from 3 to 8
+move 1 from 2 to 1
+move 4 from 3 to 9
+move 3 from 1 to 6
+move 2 from 7 to 1
+move 1 from 5 to 6
+move 1 from 3 to 8
+move 4 from 1 to 4
+move 5 from 2 to 9
+move 3 from 1 to 4
+move 18 from 9 to 7
+move 4 from 8 to 4
+move 3 from 1 to 2
+move 1 from 9 to 7
+move 1 from 4 to 7
+move 1 from 6 to 2
+move 1 from 2 to 5
+move 25 from 7 to 3
+move 7 from 4 to 2
+move 8 from 7 to 9
+move 4 from 8 to 6
+move 1 from 8 to 5
+move 4 from 6 to 5
+move 2 from 9 to 5
+move 3 from 5 to 8
+move 4 from 6 to 4
+move 12 from 3 to 5
+move 11 from 3 to 2
+move 13 from 5 to 8
+move 4 from 9 to 6
+move 7 from 4 to 9
+move 2 from 6 to 2
+move 12 from 2 to 7
+move 1 from 6 to 3
+move 1 from 5 to 6
+move 2 from 5 to 3
+move 15 from 8 to 6
+move 4 from 6 to 7
+move 1 from 5 to 1
+move 10 from 2 to 8
+move 8 from 8 to 3
+move 8 from 6 to 8
+move 2 from 7 to 6
+move 9 from 9 to 7
+move 8 from 8 to 9
+move 1 from 1 to 3
+move 1 from 2 to 7
+move 7 from 3 to 1
+move 3 from 8 to 5
+move 3 from 1 to 6
+move 7 from 9 to 2
+move 2 from 3 to 7
+move 5 from 7 to 9
+move 17 from 7 to 5
+move 2 from 7 to 6
+move 10 from 6 to 3
+move 1 from 1 to 3
+move 6 from 9 to 3
+move 1 from 2 to 9
+move 2 from 7 to 9
+move 2 from 9 to 7
+move 1 from 5 to 8
+move 1 from 8 to 5
+move 6 from 2 to 5
+move 1 from 6 to 1
+move 5 from 3 to 5
+move 1 from 6 to 8
+move 1 from 7 to 9
+move 2 from 9 to 3
+move 15 from 5 to 2
+move 2 from 1 to 8
+move 2 from 3 to 7
+move 2 from 8 to 3
+move 3 from 5 to 9
+move 1 from 8 to 6
+move 1 from 9 to 6
+move 3 from 7 to 6
+move 17 from 3 to 4
+move 1 from 1 to 2
+move 6 from 2 to 9
+move 16 from 4 to 1
+move 4 from 6 to 8
+move 9 from 5 to 6
+move 8 from 6 to 2
+move 2 from 9 to 5
+move 2 from 3 to 5
+move 1 from 6 to 2
+move 1 from 4 to 8
+move 14 from 1 to 3
+move 8 from 5 to 3
+move 20 from 3 to 1
+move 1 from 8 to 2
+move 1 from 9 to 6
+move 1 from 6 to 7
+move 1 from 7 to 3
+move 22 from 1 to 2
+move 3 from 3 to 6
+move 27 from 2 to 8
+move 2 from 2 to 8
+move 2 from 6 to 9
+move 2 from 9 to 4
+move 2 from 4 to 8
+move 1 from 1 to 3
+move 14 from 8 to 5
+move 1 from 3 to 9
+move 3 from 9 to 2
+move 5 from 2 to 8
+move 10 from 2 to 9
+move 1 from 6 to 7
+move 1 from 7 to 5
+move 7 from 5 to 2
+move 2 from 9 to 2
+move 1 from 6 to 2
+move 2 from 9 to 5
+move 3 from 5 to 6
+move 6 from 5 to 3
+move 1 from 5 to 6
+move 4 from 3 to 9
+move 2 from 9 to 8
+move 3 from 9 to 5
+move 23 from 8 to 1
+move 2 from 6 to 1
+move 1 from 5 to 7
+move 2 from 3 to 5
+move 2 from 9 to 5
+move 4 from 9 to 7
+move 2 from 9 to 4
+move 1 from 5 to 4
+move 5 from 8 to 5
+move 2 from 6 to 2
+move 3 from 7 to 3
+move 1 from 3 to 4
+move 3 from 2 to 8
+move 4 from 1 to 6
+move 2 from 6 to 3
+move 4 from 1 to 2
+move 3 from 8 to 1
+move 13 from 2 to 5
+move 4 from 3 to 2
+move 14 from 5 to 7
+move 5 from 2 to 7
+move 18 from 7 to 9
+move 4 from 4 to 7
+move 2 from 5 to 4
+move 17 from 9 to 5
+move 1 from 9 to 1
+move 1 from 7 to 2
+move 5 from 7 to 2
+move 18 from 1 to 4
+move 1 from 7 to 3
+move 1 from 3 to 6
+move 2 from 1 to 3
+move 1 from 6 to 5
+move 2 from 6 to 8
+move 1 from 8 to 9
+move 1 from 8 to 3
+move 13 from 4 to 5
+move 1 from 1 to 6
+move 3 from 2 to 4
+move 1 from 6 to 1
+move 3 from 2 to 9
+move 3 from 3 to 1
+move 5 from 4 to 5
+move 30 from 5 to 3
+move 1 from 4 to 6
+move 1 from 9 to 8
+move 1 from 9 to 6
+move 21 from 3 to 7
+move 3 from 1 to 6
+move 1 from 1 to 4
+move 1 from 9 to 6
+move 1 from 8 to 2
+move 1 from 3 to 6
+move 1 from 9 to 3
+move 5 from 4 to 8
+move 1 from 2 to 4
+move 9 from 5 to 7
+move 2 from 5 to 9
+move 2 from 8 to 2
+move 2 from 6 to 3
+move 1 from 4 to 1
+move 4 from 3 to 8
+move 2 from 9 to 2
+move 4 from 2 to 6
+move 1 from 1 to 4
+move 2 from 6 to 9
+move 2 from 5 to 4
+move 1 from 3 to 1
+move 1 from 1 to 3
+move 2 from 9 to 1
+move 5 from 3 to 5
+move 1 from 1 to 8
+move 4 from 6 to 4
+move 5 from 5 to 6
+move 18 from 7 to 5
+move 1 from 3 to 4
+move 12 from 7 to 5
+move 15 from 5 to 6
+move 1 from 5 to 8
+move 1 from 3 to 7
+move 1 from 1 to 2
+move 1 from 2 to 4
+move 1 from 7 to 9
+move 2 from 8 to 2
+move 1 from 2 to 4
+move 4 from 4 to 2
+move 1 from 2 to 1
+move 1 from 9 to 8
+move 4 from 6 to 4
+move 3 from 2 to 6
+move 1 from 2 to 6
+move 8 from 4 to 3
+move 1 from 1 to 3
+move 6 from 6 to 1
+move 1 from 3 to 6
+move 5 from 1 to 7
+move 10 from 5 to 9
+move 3 from 9 to 8
+move 7 from 6 to 2
+move 1 from 7 to 8
+move 3 from 5 to 8
+move 3 from 6 to 2
+move 6 from 8 to 9
+move 1 from 5 to 3
+move 2 from 3 to 1
+move 2 from 4 to 8
+move 6 from 6 to 9
+move 1 from 1 to 4
+move 17 from 9 to 2
+move 1 from 4 to 1
+move 2 from 7 to 8
+move 1 from 9 to 8
+move 3 from 8 to 4
+move 3 from 1 to 4
+move 9 from 8 to 2
+move 1 from 8 to 4
+move 12 from 2 to 7
+move 4 from 7 to 4
+move 1 from 8 to 1
+move 10 from 4 to 2
+move 3 from 3 to 2
+move 1 from 9 to 7
+move 11 from 7 to 3
+move 1 from 3 to 1
+move 2 from 3 to 9
+move 1 from 3 to 7
+move 2 from 1 to 9
+move 1 from 6 to 5
+move 7 from 3 to 6
+move 1 from 7 to 3
+move 3 from 3 to 4
+move 1 from 5 to 7
+move 2 from 4 to 3
+move 2 from 4 to 8
+move 1 from 7 to 6
+move 2 from 6 to 8
+move 1 from 9 to 2
+move 1 from 9 to 5
+move 1 from 5 to 1
+move 1 from 8 to 6
+move 1 from 3 to 2
+move 4 from 6 to 1
+move 5 from 1 to 4
+move 11 from 2 to 4
+move 2 from 8 to 2
+move 1 from 8 to 9
+move 27 from 2 to 5
+move 4 from 6 to 3
+move 3 from 2 to 4
+move 2 from 5 to 9
+move 1 from 5 to 7
+move 2 from 9 to 5
+move 14 from 4 to 7
+move 2 from 4 to 7
+move 3 from 4 to 8
+move 4 from 3 to 1
+move 4 from 1 to 8
+move 2 from 3 to 9
+move 2 from 9 to 3
+move 7 from 8 to 9
+move 1 from 3 to 8
+move 2 from 3 to 2
+move 25 from 5 to 9
+move 1 from 5 to 8
+move 1 from 8 to 7
+move 26 from 9 to 1
+move 23 from 1 to 5
+move 7 from 9 to 7
+move 1 from 9 to 8
+move 1 from 9 to 2
+move 5 from 7 to 1
+move 20 from 5 to 6
+move 1 from 7 to 6
+move 2 from 5 to 3
+move 1 from 8 to 6
+move 21 from 6 to 8
+move 1 from 6 to 4
+move 1 from 1 to 7
+move 2 from 1 to 6
+move 1 from 1 to 3
+move 1 from 2 to 5
+move 1 from 2 to 6
+move 2 from 7 to 6
+move 6 from 7 to 9
+move 3 from 1 to 2
+move 17 from 8 to 1
+move 1 from 4 to 1
+move 2 from 6 to 9
+move 3 from 8 to 9
+move 2 from 3 to 7
+move 2 from 9 to 8
+move 4 from 7 to 3
+move 4 from 3 to 4
+move 2 from 5 to 8
+move 4 from 8 to 4
+move 3 from 6 to 8
+move 18 from 1 to 5
+move 1 from 3 to 4
+move 3 from 2 to 4
+move 5 from 9 to 1
+move 10 from 7 to 5
+move 5 from 1 to 3
+move 5 from 3 to 5
+move 5 from 4 to 3
+move 2 from 4 to 2
+move 5 from 8 to 3
+move 25 from 5 to 2
+move 3 from 3 to 6
+move 1 from 1 to 3
+move 3 from 6 to 7
+move 1 from 4 to 2
+move 1 from 5 to 8
+move 2 from 4 to 9
+move 1 from 8 to 1
+move 20 from 2 to 7
+move 10 from 7 to 1
+move 1 from 1 to 7
+move 4 from 7 to 8
+move 5 from 5 to 4
+move 4 from 8 to 6
+move 1 from 1 to 3
+move 5 from 7 to 4
+move 2 from 1 to 5
+move 4 from 9 to 1
+move 3 from 2 to 5
+move 5 from 5 to 1
+move 1 from 9 to 1
+move 11 from 1 to 3
+move 1 from 6 to 2
+move 7 from 3 to 5
+move 11 from 3 to 7
+move 1 from 2 to 6
+move 7 from 7 to 8
+move 1 from 9 to 1
+move 2 from 3 to 1
+move 1 from 5 to 3
+move 4 from 1 to 6
+move 4 from 6 to 3
+move 9 from 4 to 5
+move 2 from 8 to 2
+move 4 from 6 to 9
+move 3 from 2 to 4
+move 1 from 8 to 6

2022/src/day5.rs

@@ -0,0 +1,339 @@
+use nom::{
+    bytes::complete::tag,
+    character::complete::{anychar, char, space0, space1, u8},
+    combinator::eof,
+    multi::{many0, many1, separated_list0, separated_list1},
+    sequence::{delimited, terminated},
+    IResult, Parser,
+};
+use std::fmt::Debug;
+
+const INPUT: &str = include_str!("../data/day5.txt");
+
+pub fn part1() -> String {
+    let (stacks, commands) = input(INPUT);
+    tops(run_commands(stacks, commands))
+}
+
+pub fn part2() -> String {
+    let (stacks, commands) = input(INPUT);
+    tops(run_commands_multicrate(stacks, commands))
+}
+
+fn run_commands(stacks: Stacks<char>, commands: Vec<Command>) -> Stacks<char> {
+    commands
+        .into_iter()
+        .fold(stacks, |stacks, command| stacks.run_command(command))
+}
+
+fn run_commands_multicrate(stacks: Stacks<char>, commands: Vec<Command>) -> Stacks<char> {
+    commands.into_iter().fold(stacks, |stacks, command| {
+        stacks.run_command_multicrate(command)
+    })
+}
+
+fn tops(stacks: Stacks<char>) -> String {
+    stacks
+        .0
+        .iter()
+        .map(|stack| stack.top())
+        .filter_map(|v| v)
+        .collect::<String>()
+}
+
+fn print_matrix(matrix: &Matrix<Option<char>>) {
+    for row in matrix.data.clone() {
+        for val in row {
+            print!(" {} ", val.unwrap_or(' '));
+        }
+        println!("");
+    }
+}
+
+#[derive(Clone, Debug, PartialEq)]
+struct Command {
+    count: u8,
+    source: u8,
+    dest: u8,
+}
+
+#[derive(Clone, Debug, PartialEq)]
+struct Matrix<T> {
+    rows: usize,
+    cols: usize,
+    data: Vec<Vec<T>>,
+}
+
+impl<T: Clone + Copy + Debug> Matrix<T> {
+    fn new(data: Vec<Vec<T>>) -> Self {
+        let rows = data.len();
+        let cols = data
+            .iter()
+            .fold(0, |max, row| std::cmp::max(max, row.len()));
+        Self { rows, cols, data }
+    }
+
+    fn rotate_cw(self) -> Self {
+        let mut data = Vec::new();
+        for col_idx in 0..self.cols {
+            let mut row = vec![];
+            for row_idx in 0..self.rows {
+                row.push(self.data[self.rows - row_idx - 1][col_idx]);
+            }
+            data.push(row);
+        }
+
+        Self {
+            rows: self.cols,
+            cols: self.rows,
+            data,
+        }
+    }
+}
+
+#[derive(Debug)]
+struct Stack<T>(Vec<T>);
+
+impl<T: Clone + Copy> Stack<T> {
+    fn from_option_vec(data: Vec<Option<T>>) -> Self {
+        Stack(data.into_iter().filter_map(|v| v).collect::<Vec<T>>())
+    }
+
+    fn push(&mut self, val: T) {
+        self.0.push(val);
+    }
+
+    fn pop(&mut self) -> Option<T> {
+        self.0.pop()
+    }
+
+    fn top(&self) -> Option<T> {
+        if self.0.len() > 0 {
+            Some(self.0[self.0.len() - 1])
+        } else {
+            None
+        }
+    }
+}
+
+#[derive(Debug)]
+struct Stacks<T>(Vec<Stack<T>>);
+
+impl<T: Clone + Copy> Stacks<T> {
+    fn run_command(mut self, cmd: Command) -> Self {
+        let Command {
+            count,
+            source,
+            dest,
+        } = cmd;
+        (0..count).for_each(|_| {
+            let val = self.0[(source - 1) as usize].pop().unwrap();
+            self.0[(dest - 1) as usize].push(val);
+        });
+        self
+    }
+
+    fn run_command_multicrate(mut self, cmd: Command) -> Self {
+        let Command {
+            count,
+            source,
+            dest,
+        } = cmd;
+
+        let mut stack = Vec::new();
+        (0..count).for_each(|_| {
+            let val = self.0[(source - 1) as usize].pop().unwrap();
+            stack.push(val);
+        });
+        while stack.len() > 0 {
+            self.0[(dest - 1) as usize].push(stack.pop().unwrap());
+        }
+
+        self
+    }
+}
+
+fn input(data: &str) -> (Stacks<char>, Vec<Command>) {
+    let (_, result) = parser(data).unwrap();
+    result
+}
+
+fn parser(input: &str) -> IResult<&str, (Stacks<char>, Vec<Command>)> {
+    let (input, rows) = many0(parse_crate_row)(input)?;
+
+    let (input, _) = parse_stack_numbers(input)?;
+
+    let (input, _) = space0(input)?;
+    let (input, _) = tag("\n")(input)?;
+
+    let (input, commands) = many1(terminated(parse_command, tag("\n").or(eof)))(input)?;
+
+    let matrix = Matrix::new(rows);
+
+    let stacks = matrix
+        .rotate_cw()
+        .data
+        .into_iter()
+        .map(|v| Stack::from_option_vec(v.clone()))
+        .collect::<Vec<Stack<char>>>();
+    Ok((input, (Stacks(stacks), commands)))
+}
+
+fn parse_command(input: &str) -> IResult<&str, Command> {
+    let (input, _) = tag("move ")(input)?;
+    let (input, count) = u8(input)?;
+    let (input, _) = tag(" from ")(input)?;
+    let (input, source) = u8(input)?;
+    let (input, _) = tag(" to ")(input)?;
+    let (input, dest) = u8(input)?;
+
+    Ok((
+        input,
+        Command {
+            count,
+            source,
+            dest,
+        },
+    ))
+}
+
+fn parse_stack_numbers(input: &str) -> IResult<&str, usize> {
+    let (input, _) = space0(input)?;
+    let (input, stack_numbers) = separated_list1(space1, u8)(input)?;
+    let (input, _) = space0(input)?;
+    let (input, _) = tag("\n")(input)?;
+    Ok((input, stack_numbers.len()))
+}
+
+fn parse_crate_row(input: &str) -> IResult<&str, Vec<Option<char>>> {
+    let (input, cells) = terminated(separated_list0(char(' '), parse_cell), tag("\n"))(input)?;
+    Ok((input, cells))
+}
+
+fn parse_cell(input: &str) -> IResult<&str, Option<char>> {
+    parse_crate.or(parse_space).parse(input)
+}
+
+fn parse_crate(input: &str) -> IResult<&str, Option<char>> {
+    delimited(char('['), anychar, char(']'))
+        .map(|c| Some(c))
+        .parse(input)
+}
+
+fn parse_space(input: &str) -> IResult<&str, Option<char>> {
+    tag("   ").map(|_| None).parse(input)
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    const TEST_DATA: &str = "    [D]    
+[N] [C]    
+[Z] [M] [P]
+ 1   2   3 
+
+move 1 from 2 to 1
+move 3 from 1 to 3
+move 2 from 2 to 1
+move 1 from 1 to 2";
+
+    fn with_input<F>(test: F)
+    where
+        F: Fn((Stacks<char>, Vec<Command>)) -> () + std::panic::UnwindSafe,
+    {
+        test(input(TEST_DATA));
+    }
+
+    #[test]
+    fn it_can_parse_test_data() {
+        with_input(|(stacks, commands)| {
+            assert_eq!(stacks.0[0].0, vec!['Z', 'N']);
+            assert_eq!(stacks.0[1].0, vec!['M', 'C', 'D']);
+            assert_eq!(stacks.0[2].0, vec!['P']);
+
+            assert_eq!(commands.len(), 4);
+            assert_eq!(
+                commands[0],
+                Command {
+                    count: 1,
+                    source: 2,
+                    dest: 1
+                }
+            );
+            assert_eq!(
+                commands[3],
+                Command {
+                    count: 1,
+                    source: 1,
+                    dest: 2
+                }
+            );
+        });
+    }
+
+    #[test]
+    fn it_can_follow_commands() {
+        with_input(|(stacks, commands)| {
+            let stacks = stacks.run_command(commands[0].clone());
+            assert_eq!(stacks.0[0].0, vec!['Z', 'N', 'D']);
+            assert_eq!(stacks.0[1].0, vec!['M', 'C']);
+            assert_eq!(stacks.0[2].0, vec!['P']);
+        });
+
+        with_input(|(stacks, commands)| {
+            let stacks = run_commands(stacks, commands);
+            assert_eq!(stacks.0[0].0, vec!['C']);
+            assert_eq!(stacks.0[1].0, vec!['M']);
+            assert_eq!(stacks.0[2].0, vec!['P', 'D', 'N', 'Z']);
+        });
+    }
+
+    #[test]
+    fn it_can_follow_multicrate_commands() {
+        with_input(|(stacks, commands)| {
+            let stacks = stacks.run_command_multicrate(commands[0].clone());
+            assert_eq!(stacks.0[0].0, vec!['Z', 'N', 'D']);
+            assert_eq!(stacks.0[1].0, vec!['M', 'C']);
+            assert_eq!(stacks.0[2].0, vec!['P']);
+        });
+
+        with_input(|(stacks, commands)| {
+            let stacks = run_commands_multicrate(stacks, commands);
+            assert_eq!(stacks.0[0].0, vec!['M']);
+            assert_eq!(stacks.0[1].0, vec!['C']);
+            assert_eq!(stacks.0[2].0, vec!['P', 'Z', 'N', 'D']);
+        });
+    }
+
+    #[test]
+    fn it_can_find_tops() {
+        with_input(|(stacks, commands)| {
+            let stacks = run_commands(stacks, commands);
+            assert_eq!(tops(stacks), "CMZ");
+        });
+    }
+
+    #[test]
+    fn it_can_rotate_symmetrix_matrix() {
+        let matrix = Matrix::new(vec![vec!['A', 'B'], vec!['C', 'D']]);
+        let expected = Matrix::new(vec![vec!['C', 'A'], vec!['D', 'B']]);
+        assert_eq!(matrix.rotate_cw(), expected);
+    }
+
+    #[test]
+    fn it_can_rotate_asymmetric_matrix() {
+        let matrix = Matrix::new(vec![
+            vec![Some('A'), Some('B'), Some('C')],
+            vec![Some('D'), Some('E'), Some('F')],
+        ]);
+        let expected = Matrix::new(vec![
+            vec![Some('D'), Some('A')],
+            vec![Some('E'), Some('B')],
+            vec![Some('F'), Some('C')],
+        ]);
+        print_matrix(&matrix);
+        print_matrix(&matrix.clone().rotate_cw());
+        assert_eq!(matrix.rotate_cw(), expected);
+    }
+}

2022/src/main.rs

@@ -2,6 +2,7 @@ mod day1;
 mod day2;
 mod day3;
 mod day4;
+mod day5;
 
 fn main() {
     let day = std::env::args().skip(1).next();
@@ -15,6 +16,8 @@ fn main() {
         Some("3b") => day3::part2(),
         Some("4a") => day4::part1(),
         Some("4b") => day4::part2(),
+        Some("5a") => day5::part1(),
+        Some("5b") => day5::part2(),
         _ => panic!("unrecognized day"),
     };