51 lines
1.3 KiB
Rust
51 lines
1.3 KiB
Rust
use aoc_runner_derive::{aoc, aoc_generator};
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#[aoc_generator(day9)]
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#[inline(always)]
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pub fn input_generator(input: &str) -> Vec<usize> {
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input
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.lines()
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.map(|l| l.trim().parse())
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.collect::<Result<Vec<usize>, _>>()
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.unwrap()
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}
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#[aoc(day9, part1)]
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#[inline(always)]
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pub fn solve_part1(input: &[usize]) -> usize {
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for (n, win) in input.windows(25).enumerate() {
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let n = n + 25;
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if n >= input.len() {
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continue;
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}
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let c = input[n];
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let mut valid = false;
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for (i1, n1) in win.iter().enumerate() {
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for (i2, n2) in win.iter().enumerate() {
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if i1 == i2 {
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continue;
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}
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if n1 + n2 == c {
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valid = true;
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}
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}
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}
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if !valid {
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return c;
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}
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}
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panic!("No match found!");
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}
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#[aoc(day9, part2)]
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#[inline(always)]
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pub fn solve_part2_fast(input: &[usize]) -> usize {
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let target_num = solve_part1(input);
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for i in 2..=input.len() {
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if let Some(w) = input.windows(i).find(|w| target_num == w.iter().sum()) {
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return w.iter().max().unwrap() + w.iter().min().unwrap();
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}
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}
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panic!("No match found!");
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}
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