Day 3: Gear Ratios

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[-] Ategon@programming.dev 2 points 2 years ago* (last edited 2 years ago)

[Rust] Harder one today, for part 1 I ended up getting stuck for a bit since I wasnt taking numbers at the end of lines into account and in part 2 I defined my gears vector in the wrong spot and spent a bit debugging that

Code

(lemmy removes some chars, all chars are in code link)

use std::fs;

fn part1(input: String) -> u32 {
    let lines = input.lines().collect::>();
    let mut sum = 0;

    for i in 0..lines.len() {
        let mut num = 0;
        let mut valid = false;
        let chars = lines[i].chars().collect::>();

        for j in 0..chars.len() {
            let character = chars[j];
            let parts = ['*', '#', '+', '$', '/', '%', '=', '-', '&amp;', '@'];

            if character.is_digit(10) {
                num = num * 10 + character.to_digit(10).unwrap();

                if i > 0 {
                    if parts.contains(&amp;lines[i - 1].chars().collect::>()[j]) {
                        valid = true;
                    }

                    if j > 0 {
                        if parts.contains(&amp;lines[i - 1].chars().collect::>()[j - 1]) {
                            valid = true;
                        }
                    }

                    if j &lt; chars.len() - 1 {
                        if parts.contains(&amp;lines[i - 1].chars().collect::>()[j + 1]) {
                            valid = true;
                        }
                    }
                }

                if i &lt; lines.len() - 1 {
                    if parts.contains(&amp;lines[i + 1].chars().collect::>()[j]) {
                        valid = true;
                    }

                    if j > 0 {
                        if parts.contains(&amp;lines[i + 1].chars().collect::>()[j - 1]) {
                            valid = true;
                        }
                    }

                    if j &lt; chars.len() - 1 {
                        if parts.contains(&amp;lines[i + 1].chars().collect::>()[j + 1]) {
                            valid = true;
                        }
                    }
                }

                if j > 0 {
                    if parts.contains(&amp;lines[i].chars().collect::>()[j - 1]) {
                        valid = true;
                    }
                }

                if j &lt; chars.len() - 1 {
                    if parts.contains(&amp;lines[i].chars().collect::>()[j + 1]) {
                        valid = true;
                    }
                }
            }
            else {
                if valid == true {
                    sum += num;
                }

                num = 0;
                valid = false;
            }

            if j == chars.len() - 1 {
                if valid == true {
                    sum += num;
                }

                num = 0;
                valid = false;
            }
        }
    }

    return sum;
}

fn part2(input: String) -> u32 {
    let lines = input.lines().collect::>();
    let mut gears: Vec&lt;(usize, usize, u32)> = Vec::new();
    let mut sum = 0;

    for i in 0..lines.len() {
        let mut num = 0;
        let chars = lines[i].chars().collect::>();
        let mut pos: (usize, usize) = (0, 0);
        let mut valid = false;

        for j in 0..chars.len() {
            let character = chars[j];
            let parts = ['*'];

            if character.is_digit(10) {
                num = num * 10 + character.to_digit(10).unwrap();

                if i > 0 {
                    if parts.contains(&amp;lines[i - 1].chars().collect::>()[j]) {
                        valid = true;
                        pos = (i - 1, j);
                    }

                    if j > 0 {
                        if parts.contains(&amp;lines[i - 1].chars().collect::>()[j - 1]) {
                            valid = true;
                            pos = (i - 1, j - 1);
                        }
                    }

                    if j &lt; chars.len() - 1 {
                        if parts.contains(&amp;lines[i - 1].chars().collect::>()[j + 1]) {
                            valid = true;
                            pos = (i - 1, j + 1);
                        }
                    }
                }

                if i &lt; lines.len() - 1 {
                    if parts.contains(&amp;lines[i + 1].chars().collect::>()[j]) {
                        valid = true;
                        pos = (i + 1, j);
                    }

                    if j > 0 {
                        if parts.contains(&amp;lines[i + 1].chars().collect::>()[j - 1]) {
                            valid = true;
                            pos = (i + 1, j - 1);
                        }
                    }

                    if j &lt; chars.len() - 1 {
                        if parts.contains(&amp;lines[i + 1].chars().collect::>()[j + 1]) {
                            valid = true;
                            pos = (i + 1, j + 1);
                        }
                    }
                }

                if j > 0 {
                    if parts.contains(&amp;lines[i].chars().collect::>()[j - 1]) {
                        valid = true;
                        pos = (i, j - 1);
                    }
                }

                if j &lt; chars.len() - 1 {
                    if parts.contains(&amp;lines[i].chars().collect::>()[j + 1]) {
                        valid = true;
                        pos = (i, j + 1);
                    }
                }
            }
            else {
                if valid == true {
                    let mut current_gear = false;
                    
                    for gear in &amp;gears {
                        if gear.0 == pos.0 &amp;&amp; gear.1 == pos.1 {
                            sum += num * gear.2;
                            current_gear = true;
                            break;
                        }
                    }
                    
                    if !current_gear {
                        let tuple_to_push = (pos.0.clone(), pos.1.clone(), num.clone());
                        gears.push((pos.0.clone(), pos.1.clone(), num.clone()));
                    }
                }

                num = 0;
                valid = false;
            }

            if j == chars.len() - 1 {
                if valid == true {
                    let mut current_gear = false;
                    
                    for gear in &amp;gears {
                        if gear.0 == pos.0 &amp;&amp; gear.1 == pos.1 {
                            sum += num * gear.2;
                            current_gear = true;
                            break;
                        }
                    }
                    
                    if !current_gear {
                        let tuple_to_push = (pos.0.clone(), pos.1.clone(), num.clone());
                        gears.push((pos.0.clone(), pos.1.clone(), num.clone()));
                    }
                }

                num = 0;
                valid = false;
            }
        }
    }

    return sum;
}

fn main() {
    let input = fs::read_to_string("data/input.txt").unwrap();

    println!("{}", part1(input.clone()));
    println!("{}", part2(input.clone()));
}

Code Link

this post was submitted on 03 Dec 2023

20 points (95.5% liked)

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