main.rs

use std::io::stdin;
use std::io::Read;
use std::rc::Rc;
use std::cell::RefCell;
use std::cmp::max;
#[derive(Debug, Copy, Clone)]
struct Position(u16, u16);
impl Position {
    fn adjacent(&self, other: &Position) -> bool { 
        max((self.0 as i16 - other.0 as i16).abs(), (self.1 as i16 - other.1 as i16).abs()) <= 1 
    }
}

#[derive(Debug)]
struct Tile {
    pos: Position,
    tile: Type,
    adjacent: RefCell<Vec<Rc<Tile>>>
}
#[derive(Debug, Copy, Clone)]
enum Type {
    Blank,
    Adjacent(u8),
    Unknown
}

fn input() -> Vec<Rc<Tile>> {
    let mut stdin = stdin();
    let mut buf = String::new();
    let _ = stdin.read_to_string(&mut buf);
    let mut tiles = Vec::<Rc<Tile>>::new();
    for (y, row) in buf.lines().enumerate() {
        for (x, column) in row.chars().enumerate() {
            let tile_type = match column {
                '?' => Type::Unknown,
                ' ' => Type::Blank,
                _ => Type::Adjacent(column.to_digit(10).unwrap() as u8)
            };
            let tile = Rc::new(Tile {
                pos: Position(x as u16, y as u16),
                tile: tile_type,
                adjacent: RefCell::new(Vec::with_capacity(8))
            });
            for tile2 in &mut tiles {
                if tile.pos.adjacent(&tile2.pos) {
                    tile.adjacent.borrow_mut().push(tile.clone());
                }
            }
            println!("{}", tile.adjacent.borrow().len());
            tiles.push(tile);
        }
    }
    tiles
}




fn main() {
    let tiles = input();
    for tile in tiles.into_iter().filter(|tile| if let Type::Adjacent(num) = tile.tile { num==tile.adjacent.borrow().len() as u8 } else { false }) {
        println!("{:?}", tile.pos);
    }
}

null

    1????
    1????
    111??
      1??
1211  1??
???21 1??
????211??
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