#[path = "../lib.rs"]
mod lib;

fn parse_input() -> (Vec<u8>, usize) {
    let mut map = vec![];
    let mut h = 0;
    for line in lib::iter_input() {
        h += 1;
        for c in line.chars() {
            map.push(c.to_digit(10).unwrap() as u8);
        }
    }
    return (map, h);
}

fn unique(a: &mut Vec<usize>) {
    a.sort();
    let mut i = 1;
    while i < a.len() {
        if a[i] == a[i - 1] {
            a.remove(i);
        } else {
            i += 1;
        }
    }
}

fn find_next(positions: Vec<usize>, map: &Vec<u8>, h: usize) -> Vec<usize> {
    let w = map.len() / h;
    let mut result = vec![];
    for i in positions.into_iter() {
        let v = map[i] - 1;
        if i / w != 0 && map[i - w] == v {
            result.push(i - w);
        }
        if i / w != h - 1 && map[i + w] == v {
            result.push(i + w);
        }
        if i % w != 0 && map[i - 1] == v {
            result.push(i - 1);
        }
        if i % w != w - 1 && map[i + 1] == v {
            result.push(i + 1);
        }
    }
    return result;
}

fn main() {
    let (map, h) = parse_input();
    let mut sum1 = 0;
    let mut sum2 = 0;

    for (i, v) in map.iter().enumerate() {
        if *v == 9 {
            let mut positions = vec![i];
            for _ in 0..9 {
                positions = find_next(positions, &map, h);
            }
            sum2 += positions.len();
            unique(&mut positions);
            sum1 += positions.len();
        }
    }

    println!("part1: {}", sum1);
    println!("part2: {}", sum2);
}