58 lines
1.6 KiB
Rust
58 lines
1.6 KiB
Rust
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const INPUT: &str = include_str!("input.txt");
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const GRID_WIDTH: i64 = 101;
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const GRID_HEIGHT: i64 = 103;
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const SQUARE_THRESHOLD: i64 = 4; // 4x4 square
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#[derive(Debug)]
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pub struct Robot {
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pub position: (i64, i64),
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pub velocity: (i64, i64),
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}
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fn main() {
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let mut robots = INPUT
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.lines()
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.map(|l| l.split_once(" v=").unwrap())
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.map(|(p, v)| {
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(
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p.trim_start_matches("p=").split_once(",").unwrap(),
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v.split_once(",").unwrap(),
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)
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})
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.map(|(p, v)| Robot {
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position: (p.0.parse().unwrap(), p.1.parse().unwrap()),
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velocity: (v.0.parse().unwrap(), v.1.parse().unwrap()),
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})
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.collect::<Vec<_>>();
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let mut i = 0u64;
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loop {
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i += 1;
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for robot in robots.iter_mut() {
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robot.position = (
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((robot.position.0 + robot.velocity.0)).rem_euclid(GRID_WIDTH),
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((robot.position.1 + robot.velocity.1)).rem_euclid(GRID_HEIGHT),
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);
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}
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// Check for square
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let square = robots.iter().map(|r| r.position).any(
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|(start_x, start_y)|
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(start_x..(start_x + SQUARE_THRESHOLD)).all(
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|x|
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(start_y..(start_y + SQUARE_THRESHOLD)).all(
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|y|
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robots.iter().any(
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|r|
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r.position == (x, y)
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)
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)
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)
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);
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if square { break; }
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}
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println!("Result: {}", i);
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}
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