year2015/
day02.rs

1use utils::prelude::*;
2
3/// Box maths.
4#[derive(Clone, Debug)]
5pub struct Day02 {
6    boxes: Vec<Box>,
7}
8
9#[derive(Clone, Debug)]
10struct Box {
11    l: u32,
12    w: u32,
13    h: u32,
14}
15
16impl Day02 {
17    pub fn new(input: &str, _: InputType) -> Result<Self, InputError> {
18        Ok(Self {
19            boxes: parser::u32()
20                .then(parser::u32().with_prefix(b'x'))
21                .then(parser::u32().with_prefix(b'x'))
22                .map(|(l, w, h)| Box { l, w, h })
23                .parse_lines(input)?,
24        })
25    }
26
27    #[must_use]
28    pub fn part1(&self) -> u32 {
29        self.boxes
30            .iter()
31            .map(|&Box { l, w, h }| {
32                (2 * l * w) + (2 * w * h) + (2 * h * l) + (l * w).min(w * h).min(h * l)
33            })
34            .sum()
35    }
36
37    #[must_use]
38    pub fn part2(&self) -> u32 {
39        self.boxes
40            .iter()
41            .map(|&Box { l, w, h }| {
42                let min = l.min(w).min(h);
43                let max = l.max(w).max(h);
44                let mid = l + w + h - min - max;
45                (2 * min) + (2 * mid) + (l * w * h)
46            })
47            .sum()
48    }
49}
50
51examples!(Day02 -> (u32, u32) [
52    {input: "2x3x4", part1: 58, part2: 34},
53    {input: "1x1x10", part1: 43, part2: 14},
54]);
year2015/day02.rs

year2015/
day02.rs
