From 65eac56f1c16e887d55c710f58e52cbfaaec6631 Mon Sep 17 00:00:00 2001
From: Bill Thiede <git@xinu.tv>
Date: Sat, 4 Dec 2021 21:47:57 -0800
Subject: [PATCH] Day 4 part 1

---
 2021/Cargo.lock          |  53 ++++
 2021/Cargo.toml          |   2 +
 2021/input/2021/day4.txt | 601 +++++++++++++++++++++++++++++++++++++++
 2021/src/day4.rs         | 294 +++++++++++++++++++
 2021/src/lib.rs          |   1 +
 5 files changed, 951 insertions(+)
 create mode 100644 2021/input/2021/day4.txt
 create mode 100644 2021/src/day4.rs

diff --git a/2021/Cargo.lock b/2021/Cargo.lock
index 88af2b2..06f126a 100644
--- a/2021/Cargo.lock
+++ b/2021/Cargo.lock
@@ -6,9 +6,20 @@ version = 3
 name = "advent2021"
 version = "0.1.0"
 dependencies = [
+ "ansi_term",
  "anyhow",
  "aoc-runner",
  "aoc-runner-derive",
+ "thiserror",
+]
+
+[[package]]
+name = "ansi_term"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d52a9bb7ec0cf484c551830a7ce27bd20d67eac647e1befb56b0be4ee39a55d2"
+dependencies = [
+ "winapi",
 ]
 
 [[package]]
@@ -115,8 +126,50 @@ dependencies = [
  "unicode-xid",
 ]
 
+[[package]]
+name = "thiserror"
+version = "1.0.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "854babe52e4df1653706b98fcfc05843010039b406875930a70e4d9644e5c417"
+dependencies = [
+ "thiserror-impl",
+]
+
+[[package]]
+name = "thiserror-impl"
+version = "1.0.30"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "aa32fd3f627f367fe16f893e2597ae3c05020f8bba2666a4e6ea73d377e5714b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "unicode-xid"
 version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8ccb82d61f80a663efe1f787a51b16b5a51e3314d6ac365b08639f52387b33f3"
+
+[[package]]
+name = "winapi"
+version = "0.3.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
+dependencies = [
+ "winapi-i686-pc-windows-gnu",
+ "winapi-x86_64-pc-windows-gnu",
+]
+
+[[package]]
+name = "winapi-i686-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
+
+[[package]]
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
diff --git a/2021/Cargo.toml b/2021/Cargo.toml
index 0b27eb0..28957a2 100644
--- a/2021/Cargo.toml
+++ b/2021/Cargo.toml
@@ -6,6 +6,8 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+ansi_term = "0.12.1"
 anyhow = "1.0.45"
 aoc-runner = "0.3.0"
 aoc-runner-derive = "0.3.0"
+thiserror = "1.0.30"
diff --git a/2021/input/2021/day4.txt b/2021/input/2021/day4.txt
new file mode 100644
index 0000000..ec32ed7
--- /dev/null
+++ b/2021/input/2021/day4.txt
@@ -0,0 +1,601 @@
+72,99,88,8,59,61,96,92,2,70,1,32,18,10,95,33,20,31,66,43,26,24,91,44,11,15,48,90,27,29,14,68,3,50,69,74,54,4,16,55,64,12,73,80,58,83,6,87,30,41,25,39,93,60,9,81,63,75,46,19,78,51,21,28,94,7,17,42,53,13,97,98,34,76,89,23,86,52,79,85,67,84,47,22,37,65,71,49,82,40,77,36,62,0,56,45,57,38,35,5
+
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diff --git a/2021/src/day4.rs b/2021/src/day4.rs
new file mode 100644
index 0000000..5b7850e
--- /dev/null
+++ b/2021/src/day4.rs
@@ -0,0 +1,294 @@
+//! --- Day 4: Giant Squid ---
+//! You're already almost 1.5km (almost a mile) below the surface of the ocean, already so deep that you can't see any sunlight. What you can see, however, is a giant squid that has attached itself to the outside of your submarine.
+//!
+//! Maybe it wants to play bingo?
+//!
+//! Bingo is played on a set of boards each consisting of a 5x5 grid of numbers. Numbers are chosen at random, and the chosen number is marked on all boards on which it appears. (Numbers may not appear on all boards.) If all numbers in any row or any column of a board are marked, that board wins. (Diagonals don't count.)
+//!
+//! The submarine has a bingo subsystem to help passengers (currently, you and the giant squid) pass the time. It automatically generates a random order in which to draw numbers and a random set of boards (your puzzle input). For example:
+//!
+//! 7,4,9,5,11,17,23,2,0,14,21,24,10,16,13,6,15,25,12,22,18,20,8,19,3,26,1
+//!
+//! 22 13 17 11  0
+//!  8  2 23  4 24
+//! 21  9 14 16  7
+//!  6 10  3 18  5
+//!  1 12 20 15 19
+//!
+//!  3 15  0  2 22
+//!  9 18 13 17  5
+//! 19  8  7 25 23
+//! 20 11 10 24  4
+//! 14 21 16 12  6
+//!
+//! 14 21 17 24  4
+//! 10 16 15  9 19
+//! 18  8 23 26 20
+//! 22 11 13  6  5
+//!  2  0 12  3  7
+//! After the first five numbers are drawn (7, 4, 9, 5, and 11), there are no winners, but the boards are marked as follows (shown here adjacent to each other to save space):
+//!
+//! 22 13 17 11  0         3 15  0  2 22        14 21 17 24  4
+//!  8  2 23  4 24         9 18 13 17  5        10 16 15  9 19
+//! 21  9 14 16  7        19  8  7 25 23        18  8 23 26 20
+//!  6 10  3 18  5        20 11 10 24  4        22 11 13  6  5
+//!  1 12 20 15 19        14 21 16 12  6         2  0 12  3  7
+//! After the next six numbers are drawn (17, 23, 2, 0, 14, and 21), there are still no winners:
+//!
+//! 22 13 17 11  0         3 15  0  2 22        14 21 17 24  4
+//!  8  2 23  4 24         9 18 13 17  5        10 16 15  9 19
+//! 21  9 14 16  7        19  8  7 25 23        18  8 23 26 20
+//!  6 10  3 18  5        20 11 10 24  4        22 11 13  6  5
+//!  1 12 20 15 19        14 21 16 12  6         2  0 12  3  7
+//! Finally, 24 is drawn:
+//!
+//! 22 13 17 11  0         3 15  0  2 22        14 21 17 24  4
+//!  8  2 23  4 24         9 18 13 17  5        10 16 15  9 19
+//! 21  9 14 16  7        19  8  7 25 23        18  8 23 26 20
+//!  6 10  3 18  5        20 11 10 24  4        22 11 13  6  5
+//!  1 12 20 15 19        14 21 16 12  6         2  0 12  3  7
+//! At this point, the third board wins because it has at least one complete row or column of marked numbers (in this case, the entire top row is marked: 14 21 17 24 4).
+//!
+//! The score of the winning board can now be calculated. Start by finding the sum of all unmarked numbers on that board; in this case, the sum is 188. Then, multiply that sum by the number that was just called when the board won, 24, to get the final score, 188 * 24 = 4512.
+//!
+//! To guarantee victory against the giant squid, figure out which board will win first. What will your final score be if you choose that board?
+
+use std::{
+    collections::{HashMap, HashSet},
+    fmt::{Debug, Error, Formatter},
+    num::ParseIntError,
+    str::FromStr,
+};
+
+use ansi_term::Color::Green;
+use anyhow::Result;
+use aoc_runner_derive::{aoc, aoc_generator};
+use thiserror::Error;
+
+#[derive(Debug, Default)]
+struct Game {
+    numbers: Vec<u64>,
+    boards: Vec<Board>,
+}
+
+#[derive(Debug, Error)]
+enum GameError {
+    #[error("couldn't parse number {0}")]
+    ParseIntError(#[from] ParseIntError),
+    #[error("couldn't parse board {0}")]
+    BoardError(#[from] BoardError),
+    #[error("unknown")]
+    Unknown,
+}
+
+impl Game {
+    // If return not None, it contains a winning board
+    fn apply_number(&mut self, number: u64) -> Option<&Board> {
+        for b in &mut self.boards {
+            b.mark(number);
+            if b.is_bingo() {
+                return Some(b);
+            }
+        }
+        None
+    }
+}
+
+impl FromStr for Game {
+    type Err = GameError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let mut it = s.split("\n\n");
+        let numbers = it
+            .next()
+            .unwrap()
+            .split(",")
+            .map(|s| s.parse())
+            .collect::<Result<_, ParseIntError>>()?;
+        let boards: Vec<_> = it.map(|s| s.parse()).collect::<Result<_, BoardError>>()?;
+        Ok(Game { numbers, boards })
+    }
+}
+
+#[derive(Default)]
+struct Board {
+    numbers: HashMap<(usize, usize), u64>,
+    marked: HashSet<(usize, usize)>,
+}
+
+#[derive(Debug, Error)]
+enum BoardError {
+    #[error("couldn't parse number {0}")]
+    ParseIntError(#[from] ParseIntError),
+    #[error("unknown")]
+    Unknown,
+}
+
+impl Board {
+    fn is_bingo(&self) -> bool {
+        for y in 0..5 {
+            if (0..5).all(|x| self.marked.contains(&(x, y))) {
+                return true;
+            }
+        }
+        for x in 0..5 {
+            if (0..5).all(|y| self.marked.contains(&(x, y))) {
+                return true;
+            }
+        }
+        false
+    }
+    fn sum_uncovered(&self) -> u64 {
+        self.numbers
+            .iter()
+            .map(|((x, y), v)| {
+                if !self.marked.contains(&(*x, *y)) {
+                    *v
+                } else {
+                    0
+                }
+            })
+            .sum()
+    }
+    // Returns true if board has num.
+    fn mark(&mut self, num: u64) -> bool {
+        for ((x, y), v) in self.numbers.iter() {
+            if *v == num {
+                self.marked.insert((*x, *y));
+                return true;
+            }
+        }
+        false
+    }
+}
+
+impl Debug for Board {
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error> {
+        writeln!(f)?;
+        for y in 0..5 {
+            for x in 0..5 {
+                if self.marked.contains(&(x, y)) {
+                    let v = format!("{:3}", self.numbers[&(x, y)]);
+                    write!(f, "{}", Green.bold().paint(v))?;
+                } else {
+                    write!(f, "{:3}", self.numbers[&(x, y)])?;
+                }
+            }
+            writeln!(f, "")?;
+        }
+        Ok(())
+    }
+}
+
+impl FromStr for Board {
+    type Err = BoardError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let numbers: Vec<Vec<_>> = s
+            .split("\n")
+            .map(|l| {
+                l.split(" ")
+                    // Remove the double space that happens before single digit cells.
+                    .filter(|c| *c != "")
+                    .map(|c| c.parse())
+                    .collect::<Result<_, ParseIntError>>()
+            })
+            .collect::<Result<_, ParseIntError>>()?;
+        let numbers: HashMap<_, _> = numbers
+            .iter()
+            .enumerate()
+            .flat_map(|(y, row)| row.iter().enumerate().map(move |(x, c)| ((x, y), *c)))
+            .collect();
+        Ok(Board {
+            numbers,
+            marked: Default::default(),
+        })
+    }
+}
+
+#[aoc(day4, part1)]
+fn part1(input: &str) -> Result<u64> {
+    let mut g: Game = input.parse()?;
+    let numbers = g.numbers.clone();
+    for n in numbers {
+        if let Some(b) = g.apply_number(n) {
+            println!("winning board {:?}", b);
+            return Ok(n as u64 * b.sum_uncovered());
+        }
+    }
+    unreachable!("We should have had a winner by now");
+}
+
+/*
+#[aoc(day4, part2)]
+fn part2(depths: &[u32]) -> Result<u32> {
+todo!("part2")
+Ok(())
+}
+*/
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_board() -> Result<()> {
+        let input = r#"
+14 21 17 24  4
+10 16 15  9 19
+18  8 23 26 20
+22 11 13  6  5
+ 2  0 12  3  7
+ "#
+        .trim();
+        let mut b = Board::from_str(input)?;
+        assert!(!b.is_bingo());
+        assert!(!b.mark(100));
+
+        for num in &[7, 4, 9, 5, 11, 17, 23, 2, 0, 14, 21, 24] {
+            assert!(b.mark(*num));
+        }
+        assert!(b.is_bingo());
+        assert_eq!(b.sum_uncovered(), 188);
+        Ok(())
+    }
+
+    #[test]
+    fn test_part1() -> Result<()> {
+        let input = r#"
+7,4,9,5,11,17,23,2,0,14,21,24,10,16,13,6,15,25,12,22,18,20,8,19,3,26,1
+
+22 13 17 11  0
+ 8  2 23  4 24
+21  9 14 16  7
+ 6 10  3 18  5
+ 1 12 20 15 19
+
+ 3 15  0  2 22
+ 9 18 13 17  5
+19  8  7 25 23
+20 11 10 24  4
+14 21 16 12  6
+
+14 21 17 24  4
+10 16 15  9 19
+18  8 23 26 20
+22 11 13  6  5
+ 2  0 12  3  7
+ "#
+        .trim();
+        assert_eq!(part1(input)?, 4512);
+        Ok(())
+    }
+
+    /*
+    #[test]
+    fn test_part2()->Result<()> {
+    let input = r#"
+    "#
+    .trim();
+    assert_eq!(part2(&parse(input)?)?, TODO);
+    Ok(())
+    }
+    */
+}
diff --git a/2021/src/lib.rs b/2021/src/lib.rs
index f647adc..db1e511 100644
--- a/2021/src/lib.rs
+++ b/2021/src/lib.rs
@@ -1,6 +1,7 @@
 pub mod day1;
 pub mod day2;
 pub mod day3;
+pub mod day4;
 
 use aoc_runner_derive::aoc_lib;