advent_of_code/year2017/
day09.rs

1use crate::input::Input;
2
3pub fn solve(input: &Input) -> Result<u32, String> {
4    let mut result = 0;
5    let mut stack = Vec::new();
6    let mut ignore_next = false;
7    let mut inside_garbage = false;
8
9    for char in input.text.bytes() {
10        if ignore_next {
11            ignore_next = false;
12            continue;
13        }
14
15        match (inside_garbage, char) {
16            (false, b'<') => {
17                inside_garbage = true;
18            }
19            (false, b'{') => {
20                if input.is_part_one() {
21                    let this_score = 1 + stack.last().unwrap_or(&0);
22                    stack.push(this_score);
23                    result += this_score;
24                }
25            }
26            (false, b'}') => {
27                stack.pop();
28            }
29            (true, b'!') => {
30                ignore_next = true;
31            }
32            (true, b'>') => {
33                inside_garbage = false;
34            }
35            (true, _) => {
36                if input.is_part_two() {
37                    result += 1;
38                }
39            }
40            _ => {}
41        }
42    }
43    Ok(result)
44}
45
46#[test]
47fn tests() {
48    let real_input = include_str!("day09_input.txt");
49    test_part_one!(real_input => 11089);
50    test_part_two!(real_input => 5288);
51}
advent_of_code/year2017/day09.rs

advent_of_code/year2017/
day09.rs
