macro-ify matching days and parts

src/day1.rs

@@ -1,7 +1,7 @@
 use std::collections::VecDeque;
 
 /// Increments count if each sample is larger than the previous.
-pub fn day1_p1(input: String) {
+pub fn part1(input: String) {
     let mut prev = None;
     let mut count: u32 = 0;
     for line in input.lines() {
@@ -22,7 +22,7 @@ pub fn day1_p1(input: String) {
 /// 3-sample windowing average (no need to average, just use sum here)
 ///
 /// We need to start comparing when we have all of
-pub fn day1_p2(input: String) {
+pub fn part2(input: String) {
     let mut storage = VecDeque::with_capacity(5);
     let mut count = 0;
 

src/day2.rs

@@ -1,5 +1,6 @@
 struct Position {
     pub x: i64,
+    #[allow(dead_code)]
     pub y: i64,
     pub z: i64,
 }

src/day4.rs

@@ -0,0 +1,135 @@
+use std::convert::TryInto;
+
+struct BingoBoard {
+    board: [[u8; 5]; 5],
+    marked: [[bool; 5]; 5],
+    bingo: bool,
+}
+
+impl BingoBoard {
+    fn new(board: [[u8; 5]; 5]) -> Self {
+        Self {
+            board,
+            marked: [[false; 5]; 5],
+            bingo: false,
+        }
+    }
+
+    /// Checks to see if bingo has been achieved.
+    ///
+    /// Returns true if any row or column is fully marked. (Ignores diagonals)
+    fn check_bingo(&mut self) -> bool {
+        // Check rows
+        for row in self.marked {
+            if row.iter().all(|marked| *marked) {
+                self.bingo = true;
+                return true;
+            }
+        }
+
+        // Check columns
+        for i in 0..self.marked.len() {
+            if self.marked.iter().map(|row| row[i]).all(|marked| marked) {
+                self.bingo = true;
+                return true;
+            }
+        }
+
+        false
+    }
+
+    fn is_bingo(&self) -> bool {
+        self.bingo
+    }
+
+    /// Checks number for existance on board and marks off any instances of it.
+    fn check_number(&mut self, number: u8) {
+        for i in 0..self.board.len() {
+            for j in 0..self.board[i].len() {
+                if self.board[i][j] == number {
+                    self.marked[i][j] = true;
+                }
+            }
+        }
+    }
+
+    // Scores board based on input number
+    fn score(&self, number: u8) -> usize {
+        let mut score = 0usize;
+        for i in 0..self.board.len() {
+            for j in 0..self.board[i].len() {
+                if !self.marked[i][j] {
+                    score += self.board[i][j] as usize;
+                }
+            }
+        }
+
+        score * number as usize
+    }
+}
+
+fn parse_input(input: String) -> (Vec<u8>, Vec<BingoBoard>) {
+    let mut lines = input.lines();
+
+    let input: Vec<u8> = lines
+        .next()
+        .unwrap()
+        .split(',')
+        .map(|s| str::parse::<u8>(s).unwrap())
+        .collect();
+
+    // Keep building boards until we don't have any more lines to parse
+    let mut boards = Vec::<BingoBoard>::new();
+    while let Some(_) = lines.next() {
+        let mut board = [[0u8; 5]; 5];
+        for i in 0..board.len() {
+            let line: Vec<u8> = lines
+                .next()
+                .unwrap()
+                .split_whitespace()
+                .map(|s| str::parse::<u8>(s).unwrap())
+                .collect();
+            board[i] = line.try_into().unwrap();
+        }
+
+        boards.push(BingoBoard::new(board));
+    }
+
+    (input, boards)
+}
+
+pub fn part1(input: String) {
+    let (input, mut boards) = parse_input(input);
+
+    for call in input {
+        // Mark and check boards
+        // NOTE: making big assumption here that only one board wins
+        for board in &mut boards {
+            board.check_number(call);
+
+            if board.check_bingo() {
+                println!("Final score: {}", board.score(call));
+                return;
+            }
+        }
+    }
+}
+
+pub fn part2(input: String) {
+    let (input, mut boards) = parse_input(input);
+
+    let mut final_score = 0usize;
+    for call in input {
+        for board in &mut boards {
+            if !board.is_bingo() {
+                board.check_number(call);
+
+                if board.check_bingo() {
+                    final_score = board.score(call);
+                }
+            }
+        }
+    }
+
+    println!("Last winner's score: {}", final_score);
+}

src/main.rs

@@ -3,6 +3,7 @@ use clap::{App, Arg};
 mod day1;
 mod day2;
 mod day3;
+mod day4;
 
 fn main() {
     let matches = App::new("AOC 2021 Code")
@@ -34,24 +35,8 @@ fn main() {
 
     let input = read_input(day).unwrap();
 
-    match day {
-        1 => match part {
-            1 => day1::day1_p1(input),
-            2 => day1::day1_p2(input),
-            _ => (),
-        },
-        2 => match part {
-            1 => day2::part1(input),
-            2 => day2::part2(input),
-            _ => (),
-        },
-        3 => match part {
-            1 => day3::part1(input),
-            2 => day3::part2(input),
-            _ => (),
-        },
-        _ => println!("Day {} not completed yet!", day),
-    }
+    // TODO macro-ify
+    match_days!(1, day1, 2, day2, 3, day3, 4, day4);
 }
 
 // TODO do the inputs ever change inside of a day?
@@ -59,3 +44,19 @@ fn main() {
 fn read_input(day: u8) -> std::io::Result<String> {
     std::fs::read_to_string(format!("inputs/day{}", day))
 }
+
+#[macro_export]
+macro_rules! match_days {
+    ( $($num:expr, $day:ident),* ) => {
+        match day {
+            $(
+            $num => match part {
+                1 => $day::part1(input),
+                2 => $day::part2(input),
+                _ => println!("Part {} invalid!", part),
+            },
+            )*
+            _ => println!("Day {} not completed yet!", day),
+        }
+    };
+}