Day 2: Cube Conundrum


Megathread guidelines

  • Keep top level comments as only solutions, if you want to say something other than a solution put it in a new post. (replies to comments can be whatever)
  • Code block support is not fully rolled out yet but likely will be in the middle of the event. Try to share solutions as both code blocks and using something such as https://topaz.github.io/paste/ or pastebin (code blocks to future proof it for when 0.19 comes out and since code blocks currently function in some apps and some instances as well if they are running a 0.19 beta)

FAQ

  • What is this?: Here is a post with a large amount of details: https://programming.dev/post/6637268
  • Where do I participate?: https://adventofcode.com/
  • Is there a leaderboard for the community?: We have a programming.dev leaderboard with the info on how to join in this post: https://programming.dev/post/6631465

🔒This post will be unlocked when there is a decent amount of submissions on the leaderboard to avoid cheating for top spots

🔓 Edit: Post has been unlocked after 6 minutes

  • bugsmith@programming.dev
    ·
    edit-2
    7 months ago

    Late as always, as I'm on UK time and can't work on these until late evening.

    Part 01 and Part 02 in Rust 🦀 :

    use std::{
        env, fs,
        io::{self, BufRead, BufReader},
    };
    
    #[derive(Debug)]
    struct Sample {
        r: u32,
        g: u32,
        b: u32,
    }
    
    fn split_cube_set(set: &[&str], colour: &str) -> Option {
        match set.iter().find(|x| x.ends_with(colour)) {
            Some(item) => item
                .trim()
                .split(' ')
                .next()
                .expect("Found item is present")
                .parse::()
                .ok(),
            None => None,
        }
    }
    
    fn main() -> io::Result<()> {
        let args: Vec = env::args().collect();
        let filename = &args[1];
        let file = fs::File::open(filename)?;
        let reader = BufReader::new(file);
        let mut valid_game_ids_sum = 0;
        let mut game_power_sum = 0;
        let max_r = 12;
        let max_g = 13;
        let max_b = 14;
        for line_result in reader.lines() {
            let mut valid_game = true;
            let line = line_result.unwrap();
            let line_split: Vec<_> = line.split(':').collect();
            let game_id = line_split[0]
                .split(' ')
                .collect::>()
                .last()
                .expect("item exists")
                .parse::()
                .expect("is a number");
            let rest = line_split[1];
            let cube_sets = rest.split(';');
            let samples: Vec = cube_sets
                .map(|set| {
                    let set_split: Vec<_> = set.split(',').collect();
                    let r = split_cube_set(&set_split, "red").unwrap_or(0);
                    let g = split_cube_set(&set_split, "green").unwrap_or(0);
                    let b = split_cube_set(&set_split, "blue").unwrap_or(0);
                    Sample { r, g, b }
                })
                .collect();
            let mut highest_r = 0;
            let mut highest_g = 0;
            let mut highest_b = 0;
            for sample in &samples {
                if !(sample.r <= max_r && sample.g <= max_g && sample.b <= max_b) {
                    valid_game = false;
                }
                highest_r = u32::max(highest_r, sample.r);
                highest_g = u32::max(highest_g, sample.g);
                highest_b = u32::max(highest_b, sample.b);
            }
            if valid_game {
                valid_game_ids_sum += game_id;
            }
            game_power_sum += highest_r * highest_g * highest_b;
        }
        println!("Sum of game ids: {valid_game_ids_sum}");
        println!("Sum of game powers: {game_power_sum}");
        Ok(())
    }