advent-of-code/aoc2019/src/day11.rs

179 lines
4.2 KiB
Rust

use std::collections::HashMap;
use std::fmt::Write;
use anyhow::{bail, Result};
use crate::intcode::Intcode;
const INPUT: &str = include_str!("../input/day11.txt");
pub fn run() -> Result<String> {
let mut res = String::with_capacity(128);
writeln!(res, "part 1: {}", part1(INPUT)?)?;
writeln!(res, "part 2:")?;
part2(INPUT, &mut res)?;
Ok(res)
}
fn part1(input: &str) -> Result<usize> {
let mut robot = Robot::new(input)?;
let mut board = HashMap::new();
robot.run(&mut board)?;
Ok(board.len())
}
fn part2(input: &str, res: &mut String) -> Result<()> {
let mut robot = Robot::new(input)?;
let mut board = HashMap::new();
board.insert(robot.pos, true);
robot.run(&mut board)?;
write_board(res, board)
}
fn write_board(res: &mut String, board: HashMap<Position, bool>) -> Result<()> {
if board.is_empty() {
bail!("board was empty");
}
let min_x = board.keys().map(|p| p.x).min().unwrap();
let max_x = board.keys().map(|p| p.x).max().unwrap();
let min_y = board.keys().map(|p| p.y).min().unwrap();
let max_y = board.keys().map(|p| p.y).max().unwrap();
let width = max_x - min_x + 1;
let height = max_y - min_y + 1;
for i in 0..height {
for j in 0..width {
match board.get(&Position {
x: j + min_x,
y: i + min_y,
}) {
Some(true) => write!(res, "")?,
_ => write!(res, " ")?,
};
}
writeln!(res)?;
}
Ok(())
}
enum Direction {
Up,
Down,
Left,
Right,
}
#[derive(Clone, Copy, Hash, PartialEq, Eq)]
struct Position {
x: i64,
y: i64,
}
struct Robot {
pos: Position,
dir: Direction,
brain: Intcode,
}
impl Robot {
fn new(program: &str) -> Result<Self> {
let intcode = Intcode::new(program)?;
Ok(Robot {
pos: Position { x: 0, y: 0 },
dir: Direction::Up,
brain: intcode,
})
}
fn run(&mut self, board: &mut HashMap<Position, bool>) -> Result<()> {
while !self.brain.run_and_wait()? {
if !self.brain.output.is_empty() {
let color = self.brain.output[0];
let direction = self.brain.output[1];
match color {
0 => board.insert(self.pos, false),
1 => board.insert(self.pos, true),
_ => bail!("robot brain output different from 0 or 1"),
};
match direction {
0 => self.turn_left(),
1 => self.turn_right(),
_ => bail!("robot brain output different from 0 or 1"),
};
self.move_forward();
self.brain.output.clear();
}
let paint = match board.get(&self.pos) {
Some(true) => 1,
_ => 0,
};
self.brain.add_input(paint);
}
Ok(())
}
fn move_forward(&mut self) {
match self.dir {
Direction::Up => self.pos.y -= 1,
Direction::Down => self.pos.y += 1,
Direction::Left => self.pos.x -= 1,
Direction::Right => self.pos.x += 1,
}
}
fn turn_right(&mut self) {
match self.dir {
Direction::Up => self.dir = Direction::Right,
Direction::Right => self.dir = Direction::Down,
Direction::Down => self.dir = Direction::Left,
Direction::Left => self.dir = Direction::Up,
}
}
fn turn_left(&mut self) {
match self.dir {
Direction::Up => self.dir = Direction::Left,
Direction::Right => self.dir = Direction::Up,
Direction::Down => self.dir = Direction::Right,
Direction::Left => self.dir = Direction::Down,
}
}
}
#[cfg(test)]
mod tests {
use super::*;
const RES2: &str = include_str!("../input/day11_res.txt");
#[test]
fn part1_real() {
assert_eq!(part1(INPUT).unwrap(), 1883);
}
#[test]
fn part2_real() {
let mut res = String::with_capacity(RES2.len());
part2(INPUT, &mut res).unwrap();
assert_eq!(res.len(), RES2.len());
assert_eq!(res, RES2);
}
}