Advent of Code 2021: Day 1 (Draft vs. Final)

draft.rs

fn main() {
    let input = read_input_from_file("day01/input.txt").unwrap();

    // Part 1
    let mut count = 0;
    let mut last = -1;
    for &n in &input {
        if n > last {
            count += 1;
        }
        last = n;
    }

    // NOTE: Subtract 1 from this!!!
    println!("Part 1: {}", count);
}

final.rs

/// Advent of Code 2021: Day 1
/// https://adventofcode.com/2021/day/1

fn main() -> anyhow::Result<()> {
    let input = read_input_from_file("day01/input.txt")?;

    // Part 1
    println!("Part 1: {}", part1(&input));
}

fn part1(input: &[i32]) -> usize {
    input.windows(2)
        .filter(|w| w[1] > w[0])
        .count()
}

#[cfg(test)]
mod test {
    use super::*;

    static INPUT: [i32; 10] = [199, 200, 208, 210, 200, 207, 240, 269, 260, 263];

    #[test]
    fn test_part1() {
        assert_eq!(part1(&INPUT), 7);
    }
}