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
|
#![allow(dead_code)]
#![allow(unused_variables)]
#![allow(unused_mut)]
use std::cmp::min;
use std::collections::HashMap;
use std::env;
use std::fs::File;
use std::io::Read;
fn dfs(
mut score: i64,
sx: i64,
sy: i64,
ex: i64,
ey: i64,
m: &Vec<Vec<bool>>,
lut: &mut HashMap<(i64, i64), i64>,
) -> i64 {
if sx == ex && sy == ey {
return score;
}
if let Some(val) = lut.get(&(sx, sy)) {
if *val < score {
return 99999999999;
}
}
lut.insert((sx, sy), score);
let mut s = 99999999999;
for (dx, dy) in [(1, 0), (-1, 0), (0, 1), (0, -1)] {
let mut x = sx + dx;
let mut y = sy + dy;
if m[y as usize][x as usize] {
let a = dfs(score + 1, x, y, ex, ey, &m, lut);
s = min(s, a);
}
}
return s;
}
fn main() {
let args: Vec<String> = env::args().collect();
let filename = if args.len() == 1 {
"in/".to_owned() + args[0].split('/').last().unwrap() + ".pzl"
} else {
args[1].clone()
};
let mut f = File::open(filename).expect("cannot open file");
let mut content = String::new();
f.read_to_string(&mut content).expect("cannot read file");
let lines = content.trim_end().split("\n");
let mut sx = 0;
let mut sy = 0;
let mut ex = 0;
let mut ey = 0;
let mut m: Vec<Vec<bool>> = Vec::new();
for (y, line) in lines.enumerate() {
let mut l: Vec<bool> = Vec::new();
for (x, c) in line.chars().enumerate() {
if c == '#' {
l.push(false);
} else {
l.push(true);
}
if c == 'S' {
sx = x as i64;
sy = y as i64;
} else if c == 'E' {
ex = x as i64;
ey = y as i64;
}
}
//println!("{:?}", l);
m.push(l);
}
let width = m.len();
let height = m[0].len();
let mut res1 = 0;
let mut lut: HashMap<(i64, i64), i64> = HashMap::new();
let ref_score = dfs(0, sx, sy, ex, ey, &m, &mut lut);
for y in 1..height - 1 {
for x in 1..width - 1 {
if m[y][x] == true {
continue;
}
let mut mc = m.clone();
mc[y][x] = true;
lut.clear();
let score = dfs(0, sx, sy, ex, ey, &mc, &mut lut);
if score + 100 <= ref_score {
res1 += 1;
}
}
}
let mut from_start: HashMap<(i64, i64), i64> = HashMap::new();
let mut to_end: HashMap<(i64, i64), i64> = HashMap::new();
for y in 1..height - 1 {
for x in 1..width - 1 {
if m[y][x] == false {
continue;
}
let x = x as i64;
let y = y as i64;
lut.clear();
let score = dfs(0, sx, sy, x, y, &m, &mut lut);
from_start.insert((x, y), score);
lut.clear();
let score = dfs(0, x, y, ex, ey, &m, &mut lut);
to_end.insert((x, y), score);
}
}
let mut res2 = 0;
for y in 1..height - 1 {
for x in 1..width - 1 {
if m[y][x] == false {
continue;
}
let x = x as i64;
let y = y as i64;
let s1 = from_start.get(&(x, y)).unwrap();
for dx in -20..=20 {
for dy in -20..=20 {
let s2 = (dx as i64).abs() + (dy as i64).abs();
if s2 > 20 {
continue;
}
if let Some(s3) = to_end.get(&(x + dx, y + dy)) {
if s1 + s2 + s3 + 100 <= ref_score {
res2 += 1;
}
}
}
}
}
}
println!("res1: {}", res1);
println!("res2: {}", res2);
assert_eq!(res1, 1422);
assert_eq!(res2, 1009299);
}
|
