diff options
| -rw-r--r-- | input/day08.txt | 174 | ||||
| -rw-r--r-- | src/bin/day08.rs | 148 |
2 files changed, 322 insertions, 0 deletions
diff --git a/input/day08.txt b/input/day08.txt new file mode 100644 index 0000000..2def566 --- /dev/null +++ b/input/day08.txt @@ -0,0 +1,174 @@ +rect 1x1 +rotate row y=0 by 10 +rect 1x1 +rotate row y=0 by 10 +rect 1x1 +rotate row y=0 by 5 +rect 1x1 +rotate row y=0 by 3 +rect 2x1 +rotate row y=0 by 4 +rect 1x1 +rotate row y=0 by 3 +rect 1x1 +rotate row y=0 by 2 +rect 1x1 +rotate row y=0 by 3 +rect 2x1 +rotate row y=0 by 2 +rect 1x1 +rotate row y=0 by 3 +rect 2x1 +rotate row y=0 by 5 +rotate column x=0 by 1 +rect 4x1 +rotate row y=1 by 12 +rotate row y=0 by 10 +rotate column x=0 by 1 +rect 9x1 +rotate column x=7 by 1 +rotate row y=1 by 3 +rotate row y=0 by 2 +rect 1x2 +rotate row y=1 by 3 +rotate row y=0 by 1 +rect 1x3 +rotate column x=35 by 1 +rotate column x=5 by 2 +rotate row y=2 by 5 +rotate row y=1 by 5 +rotate row y=0 by 2 +rect 1x3 +rotate row y=2 by 8 +rotate row y=1 by 10 +rotate row y=0 by 5 +rotate column x=5 by 1 +rotate column x=0 by 1 +rect 6x1 +rotate row y=2 by 7 +rotate row y=0 by 5 +rotate column x=0 by 1 +rect 4x1 +rotate column x=40 by 2 +rotate row y=2 by 10 +rotate row y=0 by 12 +rotate column x=5 by 1 +rotate column x=0 by 1 +rect 9x1 +rotate column x=43 by 1 +rotate column x=40 by 2 +rotate column x=38 by 1 +rotate column x=15 by 1 +rotate row y=3 by 35 +rotate row y=2 by 35 +rotate row y=1 by 32 +rotate row y=0 by 40 +rotate column x=32 by 1 +rotate column x=29 by 1 +rotate column x=27 by 1 +rotate column x=25 by 1 +rotate column x=23 by 2 +rotate column x=22 by 1 +rotate column x=21 by 3 +rotate column x=20 by 1 +rotate column x=18 by 3 +rotate column x=17 by 1 +rotate column x=15 by 1 +rotate column x=14 by 1 +rotate column x=12 by 1 +rotate column x=11 by 3 +rotate column x=10 by 1 +rotate column x=9 by 1 +rotate column x=8 by 2 +rotate column x=7 by 1 +rotate column x=4 by 1 +rotate column x=3 by 1 +rotate column x=2 by 1 +rotate column x=0 by 1 +rect 34x1 +rotate column x=44 by 1 +rotate column x=24 by 1 +rotate column x=19 by 1 +rotate row y=1 by 8 +rotate row y=0 by 10 +rotate column x=8 by 1 +rotate column x=7 by 1 +rotate column x=6 by 1 +rotate column x=5 by 2 +rotate column x=3 by 1 +rotate column x=2 by 1 +rotate column x=1 by 1 +rotate column x=0 by 1 +rect 9x1 +rotate row y=0 by 40 +rotate column x=43 by 1 +rotate row y=4 by 10 +rotate row y=3 by 10 +rotate row y=2 by 5 +rotate row y=1 by 10 +rotate row y=0 by 15 +rotate column x=7 by 2 +rotate column x=6 by 3 +rotate column x=5 by 2 +rotate column x=3 by 2 +rotate column x=2 by 4 +rotate column x=0 by 2 +rect 9x2 +rotate row y=3 by 47 +rotate row y=0 by 10 +rotate column x=42 by 3 +rotate column x=39 by 4 +rotate column x=34 by 3 +rotate column x=32 by 3 +rotate column x=29 by 3 +rotate column x=22 by 3 +rotate column x=19 by 3 +rotate column x=14 by 4 +rotate column x=4 by 3 +rotate row y=4 by 3 +rotate row y=3 by 8 +rotate row y=1 by 5 +rotate column x=2 by 3 +rotate column x=1 by 3 +rotate column x=0 by 2 +rect 3x2 +rotate row y=4 by 8 +rotate column x=45 by 1 +rotate column x=40 by 5 +rotate column x=26 by 3 +rotate column x=25 by 5 +rotate column x=15 by 5 +rotate column x=10 by 5 +rotate column x=7 by 5 +rotate row y=5 by 35 +rotate row y=4 by 42 +rotate row y=2 by 5 +rotate row y=1 by 20 +rotate row y=0 by 45 +rotate column x=48 by 5 +rotate column x=47 by 5 +rotate column x=46 by 5 +rotate column x=43 by 5 +rotate column x=41 by 5 +rotate column x=38 by 5 +rotate column x=37 by 5 +rotate column x=36 by 5 +rotate column x=33 by 1 +rotate column x=32 by 5 +rotate column x=31 by 5 +rotate column x=30 by 1 +rotate column x=28 by 5 +rotate column x=27 by 5 +rotate column x=26 by 5 +rotate column x=23 by 1 +rotate column x=22 by 5 +rotate column x=21 by 5 +rotate column x=20 by 1 +rotate column x=17 by 5 +rotate column x=16 by 5 +rotate column x=13 by 1 +rotate column x=12 by 3 +rotate column x=7 by 5 +rotate column x=6 by 5 +rotate column x=3 by 1 +rotate column x=2 by 3 \ No newline at end of file diff --git a/src/bin/day08.rs b/src/bin/day08.rs new file mode 100644 index 0000000..1443ec3 --- /dev/null +++ b/src/bin/day08.rs @@ -0,0 +1,148 @@ +use std::fmt::{Display as FmtDisplay, Error as FmtError, Formatter}; +use std::io::{self, Read}; +use std::ops::{Index, IndexMut}; +use std::str::FromStr; + +enum Operation { + Rect(usize, usize), + RotateRow(usize, usize), + RotateColumn(usize, usize), +} + +impl FromStr for Operation { + type Err = (); + fn from_str(s: &str) -> Result<Self, ()> { + if s.starts_with("rect") { + let mut iter = s[5..].split('x'); + let width = iter.next().ok_or(())?.parse().map_err(|_| ())?; + let height = iter.next().ok_or(())?.parse().map_err(|_| ())?; + Ok(Operation::Rect(width, height)) + + } else if s.starts_with("rotate row") { + let mut iter = s[13..].split(" by "); + let y = iter.next().ok_or(())?.parse().map_err(|_| ())?; + let count = iter.next().ok_or(())?.parse().map_err(|_| ())?; + Ok(Operation::RotateRow(y, count)) + + } else if s.starts_with("rotate column") { + let mut iter = s[16..].split(" by "); + let x = iter.next().ok_or(())?.parse().map_err(|_| ())?; + let count = iter.next().ok_or(())?.parse().map_err(|_| ())?; + Ok(Operation::RotateColumn(x, count)) + + } else { + Err(()) + } + } +} + +struct Display { + width: usize, + height: usize, + pixels: Box<[bool]>, +} + +impl Index<(usize, usize)> for Display { + type Output = bool; + fn index(&self, index: (usize, usize)) -> &bool { + &self.pixels[index.1 * self.width + index.0] + } +} + +impl IndexMut<(usize, usize)> for Display { + fn index_mut(&mut self, index: (usize, usize)) -> &mut bool { + &mut self.pixels[index.1 * self.width + index.0] + } +} + +impl Display { + fn new(width: usize, height: usize) -> Self { + Display { + width: width, + height: height, + pixels: vec![false; width * height].into_boxed_slice(), + } + } + + fn apply(&mut self, operation: Operation) { + match operation { + Operation::Rect(width, height) => { + for y in 0..height { + for x in 0..width { + self[(x, y)] = true; + } + } + }, + + Operation::RotateRow(y, count) => { + for _ in 0..count { + let last = self[(self.width - 1, y)]; + for x in (1..self.width).rev() { + self[(x, y)] = self[(x - 1, y)]; + } + self[(0, y)] = last; + } + }, + + Operation::RotateColumn(x, count) => { + for _ in 0..count { + let last = self[(x, self.height - 1)]; + for y in (1..self.height).rev() { + self[(x, y)] = self[(x, y - 1)]; + } + self[(x, 0)] = last; + } + }, + } + } + + fn pixels_lit(&self) -> usize { + self.pixels.iter().filter(|&&p| p).count() + } +} + +impl FmtDisplay for Display { + fn fmt(&self, f: &mut Formatter) -> Result<(), FmtError> { + for y in 0..self.height { + for x in 0..self.width { + if self[(x, y)] { + write!(f, "#")?; + } else { + write!(f, " ")?; + } + } + write!(f, "\n")?; + } + Ok(()) + } +} + +fn solve(width: usize, height: usize, input: &str) -> Display { + let mut display = Display::new(width, height); + + for line in input.lines() { + display.apply(line.parse().unwrap()); + } + + display +} + +fn main() { + let mut input = String::new(); + io::stdin().read_to_string(&mut input).unwrap(); + + let display = solve(50, 6, &input); + println!("Part 1: {}", display.pixels_lit()); + println!("Part 2:\n{}", display); +} + +#[test] +fn part1() { + let input = " +rect 3x2 +rotate column x=1 by 1 +rotate row y=0 by 4 +rotate row x=1 by 1 +"; + assert_eq!(6, solve(7, 3, input.trim()).pixels_lit()); +} |