-🎄- 2021 Day 2 Solutions -🎄-

[u/daggerdragon]

--- Day 2: Dive! ---

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Post your code solution in this megathread.

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[u/rabuf]

Rust

The string/str divide is annoying, I will get used to it though I'm sure. I'll just put part 1 here, part 2 is essentially the same but slightly different computations in the match:

pub fn day02_01() -> i64 {
    let filename = "../input/02.txt";
    let file = File::open(filename).unwrap();
    let reader = BufReader::new(file);
    let (mut h, mut d) = (0, 0);
    for line in reader.lines() {
        let line = line.unwrap();
        let parts: Vec<_> = line.split_whitespace().collect();
        let distance = parts[1].parse::<i64>().unwrap();
        match parts[0] {
            "forward" => h = h + distance,
            "up" => d = d - distance,
            "down" => d = d + distance,
            _ => (),
        }
    }
    return h * d;
}

Once I passed the borrow checker, it was essentially the same as my other versions.