1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
|
use std::collections::HashSet;
static INPUT: &str = include_str!("input.txt");
fn main() {
let valueified = INPUT.chars().map(|c| match c { '<' => (-1, 0), '>' => (1, 0), '^' => (0, 1), 'v' => (0, -1), _ => (0, 0) });
let mut visited = HashSet::new();
append_visits(valueified.clone(), &mut visited);
println!("Number visited normally: {}", visited.len());
let santa_iter = valueified.clone().step_by(2);
let robot_iter = valueified.skip(1).step_by(2);
let mut visited = HashSet::new();
append_visits(santa_iter.clone(), &mut visited);
append_visits(robot_iter.clone(), &mut visited);
println!("Number visited w/ robot: {}", visited.len());
}
fn append_visits<I: Iterator<Item = (i32, i32)>>(iter: I, visited: &mut HashSet<(i32, i32)>) {
let (mut x, mut y) = (0, 0);
visited.insert((0, 0));
for (move_x, move_y) in iter {
x += move_x;
y += move_y;
visited.insert((x, y));
}
}
|
