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
|
extern crate advent_of_code_2018;
use advent_of_code_2018::*;
use std::error::Error;
use std::path::PathBuf;
// cargo watch -cs "cargo run --release --bin day_17"
struct CoordBuilder {
xmin: Option<usize>,
xmax: Option<usize>,
ymin: Option<usize>,
ymax: Option<usize>
}
#[derive(Debug)]
struct Coord {
xmin: usize,
xmax: usize,
ymin: usize,
ymax: usize
}
impl CoordBuilder {
fn new() -> CoordBuilder {
CoordBuilder {
xmin: None,
xmax: None,
ymin: None,
ymax: None
}
}
fn build(&self) -> Coord {
Coord {
xmin: self.xmin.unwrap(),
xmax: self.xmax.unwrap(),
ymin: self.ymin.unwrap(),
ymax: self.ymax.unwrap(),
}
}
}
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
enum Tile {
Clay,
RunningWater,
HalfSettledWater,
SettledWater,
Sand
}
fn main() -> Result<(), Box<Error>> {
let input = read_file(&PathBuf::from("inputs/17.txt"))?;
let clay_coords = input.iter().map(|line| {
let mut builder = CoordBuilder::new();
for split in line.split(", ") {
if split.starts_with("x=") {
let mut range_split = split
.trim_matches(|c: char| !c.is_numeric())
.split("..")
.map(|s| s.parse().unwrap());
if let Some(min) = range_split.next() {
builder.xmin = Some(min);
builder.xmax = Some(min+1);
}
if let Some(max) = range_split.next() {
builder.xmax = Some(max+1);
}
} else {
let mut range_split = split
.trim_matches(|c: char| !c.is_numeric())
.split("..")
.map(|s| s.parse().unwrap());
if let Some(min) = range_split.next() {
builder.ymin = Some(min);
builder.ymax = Some(min+1);
}
if let Some(max) = range_split.next() {
builder.ymax = Some(max+1);
}
}
}
builder.build()
}).collect::<Vec<_>>();
let range = CoordinateSystem {
xmin: clay_coords.iter().min_by_key(|coord| coord.xmin).unwrap().xmin-2,
xmax: clay_coords.iter().max_by_key(|coord| coord.xmax).unwrap().xmax+2,
ymin: clay_coords.iter().min_by_key(|coord| coord.ymin).unwrap().ymin,
ymax: clay_coords.iter().max_by_key(|coord| coord.ymax).unwrap().ymax
};
debug!(range);
let mut map = vec!(Tile::Sand; range.vector_size());
for coord in clay_coords {
for y in coord.ymin..coord.ymax {
for x in coord.xmin..coord.xmax {
map[range.to_vec(x, y)] = Tile::Clay;
}
}
}
debug!(map[range.to_vec(500, range.ymin)]);
map[range.to_vec(500, range.ymin)] = Tile::RunningWater;
let mut last_iter = Vec::new();
while last_iter != map {
last_iter = map.clone();
for y in range.ymin..range.ymax-1 {
for x in range.xmin..range.xmax {
match map[range.to_vec(x, y)] {
Tile::RunningWater => {
if map[range.to_vec(x, y+1)] == Tile::Sand {
map[range.to_vec(x, y+1)] = Tile::RunningWater;
}
if map[range.to_vec(x-1, y)] == Tile::Sand && (map[range.to_vec(x, y+1)] == Tile::Clay || map[range.to_vec(x, y+1)] == Tile::SettledWater) {
map[range.to_vec(x-1, y)] = Tile::RunningWater;
}
if map[range.to_vec(x+1, y)] == Tile::Sand && (map[range.to_vec(x, y+1)] == Tile::Clay || map[range.to_vec(x, y+1)] == Tile::SettledWater) {
map[range.to_vec(x+1, y)] = Tile::RunningWater;
}
if (map[range.to_vec(x-1, y)] == Tile::Clay || map[range.to_vec(x-1, y)] == Tile::HalfSettledWater) && (map[range.to_vec(x, y+1)] == Tile::Clay || map[range.to_vec(x, y+1)] == Tile::SettledWater) {
map[range.to_vec(x, y)] = Tile::HalfSettledWater;
}
},
Tile::HalfSettledWater => {
if map[range.to_vec(x+1, y)] == Tile::Clay {
for xleft in 0.. {
if map[range.to_vec(x-xleft, y)] == Tile::HalfSettledWater {
map[range.to_vec(x-xleft, y)] = Tile::SettledWater;
} else {
break;
}
}
}
},
_ => {}
}
}
}
}
let water_tiles = map.iter()
.filter(|&&t| t == Tile::RunningWater || t == Tile::SettledWater || t == Tile::HalfSettledWater)
.count();
debug!(water_tiles);
let settled_water_tiles = map.iter()
.filter(|&&t| t == Tile::SettledWater)
.count();
debug!(settled_water_tiles);
Ok(())
}
#[derive(Debug)]
struct CoordinateSystem {
xmin: usize,
xmax: usize,
ymin: usize,
ymax: usize
}
impl CoordinateSystem {
fn vector_size(&self) -> usize {
(self.xmax - self.xmin) * (self.ymax - self.ymin)
}
fn to_vec(&self, x: usize, y: usize) -> usize {
((y - self.ymin) * (self.xmax - self.xmin)) + (x - self.xmin)
}
}
|
