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Advent of Code solutions
1use advent_core::{day_stuff, ex_for_day, Day};
2use utils::misc::{all_combos_remove_one, follows_diff_range, FollowRangeResult};
3
4pub struct Day2;
5
6fn line_valid(line: &[i64]) -> bool {
7 let res = follows_diff_range(line, -3..4, true, false);
8 matches!(
9 res,
10 FollowRangeResult::Increasing | FollowRangeResult::Decreasing
11 )
12}
13
14impl Day for Day2 {
15 day_stuff!(2, "2", "4", Vec<Vec<i64>>);
16
17 fn part_1(input: Self::Input) -> Option<String> {
18 Some(
19 input
20 .into_iter()
21 .filter(|v| line_valid(v))
22 .count()
23 .to_string(),
24 )
25 }
26
27 fn part_2(input: Self::Input) -> Option<String> {
28 Some(
29 input
30 .into_iter()
31 .filter(|line| {
32 line_valid(line)
33 || all_combos_remove_one(line).any(|combo| {
34 let v = combo.copied().collect::<Vec<_>>();
35 line_valid(&v)
36 })
37 })
38 .count()
39 .to_string(),
40 )
41 }
42
43 fn parse_input(input: &str) -> Self::Input {
44 input
45 .split('\n')
46 .map(|l| {
47 l.split_ascii_whitespace()
48 .map(|x| x.parse::<i64>().unwrap())
49 .collect()
50 })
51 .collect()
52 }
53}