2021: day01: refacto

This commit is contained in:
Antoine Martin 2021-12-01 10:57:51 +01:00
parent 613b240211
commit 3aa37aff10

View file

@ -19,7 +19,19 @@ fn part1(input: &str) -> Result<usize> {
.map(|line| line.parse::<u64>().map_err(anyhow::Error::new)) .map(|line| line.parse::<u64>().map_err(anyhow::Error::new))
.collect::<Result<Vec<_>>>()?; .collect::<Result<Vec<_>>>()?;
Ok(measurements.windows(2).filter(|w| w[0] < w[1]).count()) Ok(count_increases(measurements.iter()))
}
fn count_increases<I, C>(numbers: I) -> usize
where
C: std::cmp::PartialOrd,
I: Iterator<Item = C> + Clone,
{
numbers
.clone()
.zip(numbers.skip(1))
.filter(|(a, b)| a < b)
.count()
} }
fn part2(input: &str) -> Result<usize> { fn part2(input: &str) -> Result<usize> {
@ -28,20 +40,9 @@ fn part2(input: &str) -> Result<usize> {
.map(|line| line.parse::<u64>().map_err(anyhow::Error::new)) .map(|line| line.parse::<u64>().map_err(anyhow::Error::new))
.collect::<Result<Vec<_>>>()?; .collect::<Result<Vec<_>>>()?;
let mut increases = 0; Ok(count_increases(
let mut prev: Option<u64> = None; measurements.windows(3).map(|w| w.iter().sum::<u64>()),
))
for window in measurements.windows(3) {
let sum = window.iter().sum();
if let Some(prev) = prev {
if prev < sum {
increases += 1;
}
}
prev = Some(sum);
}
Ok(increases)
} }
#[cfg(test)] #[cfg(test)]