59 lines
1.6 KiB
Rust
59 lines
1.6 KiB
Rust
#![feature(test, try_blocks)]
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extern crate test;
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use aoc2023::{boilerplate, common::*};
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const DAY: usize = 4;
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type I = u32;
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type Parsed = Vec<(Vec<I>, Vec<I>)>;
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fn parse_input(raw: &str) -> Parsed {
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raw.lines()
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.filter_map(|l| {
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let (w, m) = l.after(": ").split_once(" | ")?;
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Some((w.split_whitespace().map(parse_num).collect(), m.split_whitespace().map(parse_num).collect()))
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})
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.collect()
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}
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fn winning_numbers((winning, mine): &(Vec<I>, Vec<I>)) -> usize {
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mine.iter().filter(|n| winning.contains(n)).count()
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}
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const BASE: I = 2;
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fn score(n: usize) -> Option<I> {
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Some(BASE.pow(n.checked_sub(1)? as u32))
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}
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fn part1(parsed: &Parsed) -> I {
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parsed.iter().map(winning_numbers).filter_map(score).sum()
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}
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fn part2(parsed: &Parsed) -> I {
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let mut cards = vec![1; parsed.len()];
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for (i, card) in parsed.iter().enumerate() {
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let _: Option<()> = try {
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for j in 1..=winning_numbers(card) {
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*cards.get_mut(i + j)? += cards[i];
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}
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};
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}
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cards.iter().sum()
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}
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boilerplate! {
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TEST_INPUT == "\
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Card 1: 41 48 83 86 17 | 83 86 6 31 17 9 48 53
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Card 2: 13 32 20 16 61 | 61 30 68 82 17 32 24 19
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Card 3: 1 21 53 59 44 | 69 82 63 72 16 21 14 1
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Card 4: 41 92 73 84 69 | 59 84 76 51 58 5 54 83
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Card 5: 87 83 26 28 32 | 88 30 70 12 93 22 82 36
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Card 6: 31 18 13 56 72 | 74 77 10 23 35 67 36 11",
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tests: {
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part1: { TEST_INPUT => 13 },
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part2: { TEST_INPUT => 30 },
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},
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bench1 == 20407,
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bench2 == 23806951,
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bench_parse: Vec::len => 192,
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}
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