46 lines
1 KiB
Rust
46 lines
1 KiB
Rust
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use std::fmt::Write;
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use anyhow::Result;
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const INPUT: &str = include_str!("../input/day01.txt");
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pub fn run() -> Result<String> {
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let mut res = String::with_capacity(128);
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writeln!(res, "part 1: {}", part1(INPUT)?)?;
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writeln!(res, "part 2: {}", part2(INPUT)?)?;
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Ok(res)
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}
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fn part1(input: &str) -> Result<usize> {
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let measurements = input
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.lines()
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.map(|line| line.parse::<u64>().map_err(anyhow::Error::new))
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.collect::<Result<Vec<_>>>()?;
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Ok(measurements.windows(2).filter(|w| w[0] < w[1]).count())
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}
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fn part2(input: &str) -> Result<usize> {
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let measurements = input
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.lines()
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.map(|line| line.parse::<u64>().map_err(anyhow::Error::new))
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.collect::<Result<Vec<_>>>()?;
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let mut increases = 0;
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let mut prev: Option<u64> = None;
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for window in measurements.windows(3) {
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let sum = window.iter().sum();
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if let Some(prev) = prev {
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if prev < sum {
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increases += 1;
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}
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}
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prev = Some(sum);
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}
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Ok(increases)
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}
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