-
Notifications
You must be signed in to change notification settings - Fork 0
/
mod.rs
181 lines (152 loc) · 4.19 KB
/
mod.rs
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
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
use anyhow::{Context, Error, Result};
use std::{cmp::max, str::FromStr};
use crate::utils::AocError::*;
use Cube::*;
#[derive(Debug)]
pub enum Cube {
Red(u32),
Green(u32),
Blue(u32),
}
impl FromStr for Cube {
type Err = Error;
// Parse '3 blue' or '13 red'
fn from_str(s: &str) -> Result<Self> {
let mut split = s.trim().split(' ').map(|s| s.trim());
let num = split
.next()
.map(|s| s.parse::<u32>())
.ok_or(GenericError)
.context("Could not parse input, expected number")??;
let what = split
.next()
.ok_or(GenericError)
.context("Could not parse input, expected color")?;
Ok(match what {
"blue" => Blue(num),
"red" => Red(num),
"green" => Green(num),
_ => Err(GenericError).context("Unknown color")?,
})
}
}
#[derive(Debug)]
pub struct Draw {
cubes: Vec<Cube>,
}
impl FromStr for Draw {
type Err = Error;
// Parse '3 red, 5 blue, 1 green'
fn from_str(s: &str) -> Result<Self> {
let cubes = s
.split(',')
.map(Cube::from_str)
.collect::<Result<Vec<_>>>()?;
Ok(Self { cubes })
}
}
impl Draw {
fn is_valid_for_part1(&self) -> bool {
self.cubes.iter().all(|e| match e {
Red(v) => *v <= 12,
Green(v) => *v <= 13,
Blue(v) => *v <= 14,
})
}
}
#[derive(Debug)]
pub struct Game {
id: u32,
draws: Vec<Draw>,
}
impl FromStr for Game {
type Err = Error;
// Parse a single input line
fn from_str(s: &str) -> Result<Self> {
let mut split = s.split(':');
let id = split
.next()
.ok_or(GenericError)
.context("Could not read game name")?
.split(' ')
.nth(1)
.map(|v| v.parse::<u32>())
.ok_or(GenericError)
.context("Could not read game id")??;
let draws = split
.next()
.ok_or(GenericError)
.context("Could not parse draws")?
.split(';')
.map(Draw::from_str)
.collect::<Result<Vec<_>>>()?;
Ok(Game { id, draws })
}
}
impl Game {
pub fn is_valid_for_part1(&self) -> bool {
self.draws.iter().map(|v| v.is_valid_for_part1()).all(|b| b)
}
pub fn power(&self) -> u32 {
let mut max_red = 0;
let mut max_blue = 0;
let mut max_green = 0;
for set in &self.draws {
for cube in &set.cubes {
match cube {
Red(v) => max_red = max(max_red, *v),
Green(v) => max_green = max(max_green, *v),
Blue(v) => max_blue = max(max_blue, *v),
}
}
}
max_red * max_green * max_blue
}
}
#[aoc_generator(day02)]
pub fn input_generator(input: &str) -> Result<Vec<Game>> {
input
.lines()
.filter(|s| !s.is_empty())
.map(Game::from_str)
.collect::<Result<Vec<_>>>()
}
#[aoc(day02, part1)]
pub fn solve_part1(input: &[Game]) -> Result<u32> {
let hash = input
.iter()
.map(|g| (g.id, g.is_valid_for_part1()))
.filter(|(_, v)| *v)
.map(|(i, _)| i)
.sum::<u32>();
Ok(hash)
}
#[aoc(day02, part2)]
pub fn solve_part2(input: &[Game]) -> Result<u32> {
let result = input.iter().map(|g| g.power()).sum::<u32>();
Ok(result)
}
#[cfg(test)]
mod test {
use super::*;
fn sample() -> &'static str {
"Game 1: 3 blue, 4 red; 1 red, 2 green, 6 blue; 2 green
Game 2: 1 blue, 2 green; 3 green, 4 blue, 1 red; 1 green, 1 blue
Game 3: 8 green, 6 blue, 20 red; 5 blue, 4 red, 13 green; 5 green, 1 red
Game 4: 1 green, 3 red, 6 blue; 3 green, 6 red; 3 green, 15 blue, 14 red
Game 5: 6 red, 1 blue, 3 green; 2 blue, 1 red, 2 green"
}
fn input() -> Result<Vec<Game>> {
input_generator(sample())
}
#[test]
fn part1_sample() -> Result<()> {
let data = input()?;
Ok(assert_eq!(8, solve_part1(&data)?))
}
#[test]
fn part2_sample() -> Result<()> {
let data = input()?;
Ok(assert_eq!(2286, solve_part2(&data)?))
}
}