67 lines
1.7 KiB
Rust
67 lines
1.7 KiB
Rust
use std::collections::HashMap;
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use std::io::{self, BufRead};
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struct Movement {
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pub direction: char,
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pub distance: u16,
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}
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impl Movement {
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pub fn new(raw: &str) -> Self {
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Self {
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direction: raw.chars().nth(0).unwrap(),
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distance: raw.get(1..).unwrap().parse().unwrap(),
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}
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}
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}
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fn make_step(x: &mut i32, y: &mut i32, steps: &mut i32, dir: char) {
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*steps += 1;
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match dir {
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'U' => *y += 1,
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'D' => *y -= 1,
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'L' => *x += 1,
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_ => *x -= 1,
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};
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}
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pub fn main() {
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let stdin = io::stdin();
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let mut input = stdin.lock().lines().map(|s| {
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s.unwrap()
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.split(',')
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.map(|m| Movement::new(m))
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.collect::<Vec<_>>()
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});
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let (first_wire, second_wire) = (input.next().unwrap(), input.next().unwrap());
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let mut first_wire_positions = HashMap::new();
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let (mut x, mut y, mut steps) = (0, 0, 0);
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for m in first_wire {
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for _ in 0..m.distance {
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make_step(&mut x, &mut y, &mut steps, m.direction);
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first_wire_positions.insert((x, y), steps);
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}
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}
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x = 0;
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y = 0;
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steps = 0;
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let mut intersections = HashMap::new();
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for m in second_wire {
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for _ in 0..m.distance {
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make_step(&mut x, &mut y, &mut steps, m.direction);
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first_wire_positions
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.get(&(x, y))
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.map(|s| intersections.insert((x, y), s + steps));
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}
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}
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println!(
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"Part 1: {}",
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intersections
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.keys()
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.map(|(x, y)| x.abs() + y.abs())
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.min()
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.unwrap()
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);
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println!("Part 2: {}", intersections.values().min().unwrap());
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}
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