partOne.py

from common import *
from typing import Dict, Tuple


def count_neighbours(
    matrix: Dict[Tuple[int, int, int], str], position: Tuple[int, int, int]
) -> int:
    num_neighbours = 0
    x, y, z = position
    for (x_delta, y_delta, z_delta) in translation_vectors_3d:
        if (
            matrix.get((x + x_delta, y + y_delta, z + z_delta), inactive_marker)
            == active_marker
        ):
            num_neighbours += 1
    return num_neighbours


def iterate(matrix: Dict[Tuple[int, int, int], str]) -> Dict[Tuple[int, int, int], str]:
    new = {}

    # get min/max for x, y and z values
    keys = list(matrix)
    _, _, min_z = min(keys, key=lambda x: x[2])
    _, _, max_z = max(keys, key=lambda x: x[2])
    _, min_y, _ = min(keys, key=lambda x: x[1])
    _, max_y, _ = max(keys, key=lambda x: x[1])
    min_x, _, _ = min(keys, key=lambda x: x[0])
    max_x, _, _ = max(keys, key=lambda x: x[0])

    for z in range(min_z - 2, max_z + 2):
        for y in range(min_y - 2, max_y + 2):
            for x in range(min_x - 2, max_x + 2):
                num_neighbours = count_neighbours(matrix, (x, y, z))
                current_state = matrix.get((x, y, z), inactive_marker)
                if (
                    num_neighbours == 2 and current_state == active_marker
                ) or num_neighbours == 3:
                    new[(x, y, z)] = active_marker

    return new


def partOne(instr: str) -> int:
    matrix = parse(instr, lambda x, y: (x, y, 0))

    for _ in range(6):
        matrix = iterate(matrix)

    return len(matrix)