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use std::collections::HashSet;
use std::io::{self, Read};
use std::ops::Add;
#[derive(Clone, Copy, PartialEq, Eq, Hash)]
struct Point(i32, i32);
impl Point {
fn left(self) -> Self {
Point(self.1, -self.0)
}
fn right(self) -> Self {
Point(-self.1, self.0)
}
fn distance(self, other: Self) -> i32 {
(self.0 - other.0).abs() + (self.1 - other.1).abs()
}
}
impl Add for Point {
type Output = Self;
fn add(self, rhs: Self) -> Self {
Point(self.0 + rhs.0, self.1 + rhs.1)
}
}
fn main() {
let mut input = String::new();
io::stdin().read_to_string(&mut input).unwrap();
let mut position = Point(0, 0);
let mut direction = Point(0, -1);
let mut visited = HashSet::new();
let mut collision = None;
for instruction in input.trim().split(", ") {
let (turn, count) = instruction.split_at(1);
if turn == "L" {
direction = direction.left();
} else {
direction = direction.right();
}
let count: i32 = count.parse().unwrap();
for _ in 0..count {
position = position + direction;
if !visited.insert(position) && collision.is_none() {
collision = Some(position);
}
}
}
println!("Part 1: {}", position.distance(Point(0, 0)));
if let Some(point) = collision {
println!("Part 2: {}", point.distance(Point(0, 0)));
}
}
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