blob: caf578b0cd290086ff4c6350f0d49d3e7c6489ac (
plain)
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
|
#![allow(dead_code)]
#![allow(unused_variables)]
#![allow(unused_mut)]
use std::fs::File;
use std::io::Read;
fn main() {
// let filename = "in/day04.ref";
let filename = "in/day04.pzl";
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: Vec<_> = content.trim_end().split('\n').collect();
// println!("{:?}", lines);
let mut res1 = 0;
let mut copies = vec![1; lines.len()];
for (i, line) in lines.into_iter().enumerate() {
let (first, rest) = line.split_once(":").unwrap();
let game_num = first.split_once(" ").unwrap().1;
let (win, actual) = rest.split_once("|").unwrap();
let parse = |a: &str| {
a.split(" ")
.filter_map(|x| x.parse().ok())
.collect::<Vec<u32>>()
};
let count = parse(actual)
.iter()
.filter(|x| parse(win).contains(x))
.count();
if count > 0 {
res1 += 1 << (count - 1);
}
for j in i..i + count {
copies[j + 1] += copies[i];
}
}
let res2: u32 = copies.iter().sum();
println!("res1: {}", res1);
println!("res2: {}", res2);
assert_eq!(res1, 21919);
assert_eq!(res2, 9881048);
}
|
