adventofcode/src/bin/2024/04.rs

use std::ops::Neg;

#[allow(unused_variables)]
#[allow(unused_imports)]
use advent_of_code::{include_data, include_example};
use advent_of_code::{
    matrix,
    strings::{convert_to_array, line_to_char},
};

include_example!(DATA 2024 04);

#[derive(Debug, Clone, Copy, PartialEq, PartialOrd, Eq, Ord)]
struct TextPos {
    startx: usize,
    starty: usize,
    endx: usize,
    endy: usize,
    length: usize,
}

#[inline]
fn dist(a: (usize, usize), b: (usize, usize)) -> (i32, i32) {
    (a.0 as i32 - b.0 as i32, a.1 as i32 - b.1 as i32)
}

#[inline]
fn dist_abs(a: (usize, usize), b: (usize, usize)) -> (usize, usize) {
    let t = dist(a, b);
    (t.0.abs() as usize, t.1.abs() as usize)
}

impl TextPos {
    const fn center(self) -> (usize, usize) {
        (
            self.startx.saturating_add(self.endx).div_ceil(2),
            self.starty.saturating_add(self.endy).div_ceil(2),
        )
    }

    fn crossing(self, other: &&Self) -> bool {
        if self.length != other.length && self.length != 3 {
            todo!()
        }
        if self.center() != other.center() {
            return false;
        }
        true
    }
}

#[test]
fn test_crossing() {
    let cases = [
        (
            TextPos {
                startx: 0,
                starty: 0,
                endx: 2,
                endy: 2,
                length: 3,
            },
            TextPos {
                startx: 0,
                starty: 0,
                endx: 2,
                endy: 2,
                length: 3,
            },
            true,
        ),
        (
            TextPos {
                startx: 1,
                starty: 0,
                endx: 1,
                endy: 2,
                length: 3,
            },
            TextPos {
                startx: 0,
                starty: 1,
                endx: 2,
                endy: 1,
                length: 3,
            },
            true,
        ),
        (
            TextPos {
                startx: 0,
                starty: 0,
                endx: 2,
                endy: 0,
                length: 3,
            },
            TextPos {
                startx: 1,
                starty: 0,
                endx: 2,
                endy: 0,
                length: 3,
            },
            false,
        ),
    ];
    for case in cases {
        assert_eq!(case.0.crossing(&&case.1), case.2)
    }
}

fn valid(x: usize, y: i32, max: usize) -> Option<usize> {
    let tmp = if y < 0 {
        x.checked_sub(y.neg() as usize)
    } else {
        x.checked_add(y as usize)
    };
    if let Some(xi) = tmp {
        if xi < max {
            return Some(xi);
        }
    }
    None
}

fn validxy(
    x: usize,
    y: usize,
    modx: i32,
    mody: i32,
    heigth: usize,
    length: usize,
) -> Option<(usize, usize)> {
    if let Some(xi) = valid(x, modx, length) {
        if let Some(yi) = valid(y, mody, heigth) {
            return Some((xi, yi));
        }
    }
    None
}

fn find_text(data: Vec<Vec<char>>, length: usize, heigth: usize, text: &str) -> (usize, usize) {
    let first: char = text.chars().nth(0).unwrap();
    let mut amount = 0;
    let mut found;
    let mut character;
    let mut chars;
    let mut coords = Vec::new();
    let mut currentpos;
    for row in 0..heigth {
        for column in 0..length {
            let char = data[row][column];
            if char != first {
                continue;
            }

            for (x, y) in matrix(false, true, true) {
                if x == y && y == 0 {
                    continue;
                }
                found = 1;
                chars = text.chars();
                chars.next();
                loop {
                    character = chars.next();
                    if character == None {
                        amount += 1;
                        currentpos = TextPos {
                            startx: row,
                            starty: column,
                            endx: (row as i32 + x * found) as usize,
                            endy: (column as i32 + y * found) as usize,
                            length: text.len(),
                        };
                        coords.push(currentpos);
                        break;
                    }
                    if let Some((posmodx, posmody)) =
                        validxy(row, column, x * found, y * found, length, heigth)
                    {
                        if data[posmodx][posmody] == character.unwrap() {
                            found += 1;
                        } else {
                            break;
                        }
                    } else {
                        break;
                    }
                }
            }
        }
    }
    let mut xtexts = Vec::new();
    for node in coords.clone() {
        for o in coords.iter().filter(|other| node.crossing(other)) {
            let other = *o;
            if node == other {
                continue;
            }
            let x = (node.min(other), node.max(other));
            if !xtexts.contains(&x) {
                xtexts.push(x);
            }
        }
    }
    println!("{:?}", xtexts);
    (amount, xtexts.len())
}

fn main() {
    let table = convert_to_array(DATA, line_to_char);
    let length = table[0].len();
    let (amount, _) = find_text(table.clone(), length, table.len(), "XMAS");
    println!("There are {} XMAS in text", amount);
    let (amount, amount_cross) = find_text(table.clone(), length, table.len(), "MAS");
    println!(
        "There are {} MAS in text, are {} crossed",
        amount, amount_cross
    );
}