advent-of-code/2022/day18.py

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2022-12-18 08:57:35 +00:00
# -*- encoding: utf-8 -*-
import sys
from typing import FrozenSet
import numpy as np
xyz = np.asarray(
[
tuple(int(x) for x in row.split(",")) # type: ignore
for row in sys.stdin.read().splitlines()
]
)
xyz = xyz - xyz.min(axis=0) + 1
cubes = np.zeros(xyz.max(axis=0) + 3, dtype=bool)
cubes[xyz[:, 0], xyz[:, 1], xyz[:, 2]] = True
n_dims = len(cubes.shape)
faces = [(-1, 0, 0), (1, 0, 0), (0, -1, 0), (0, 1, 0), (0, 0, -1), (0, 0, 1)]
answer_1 = sum(
1 for x, y, z in xyz for dx, dy, dz in faces if not cubes[x + dx, y + dy, z + dz]
)
print(f"answer 1 is {answer_1}")
visited = np.zeros_like(cubes, dtype=bool)
queue = [(0, 0, 0)]
n_faces = 0
while queue:
x, y, z = queue.pop(0)
if visited[x, y, z]:
continue
visited[x, y, z] = True
for dx, dy, dz in faces:
nx, ny, nz = x + dx, y + dy, z + dz
if not all(n >= 0 and n < cubes.shape[i] for i, n in enumerate((nx, ny, nz))):
continue
if visited[nx, ny, nz]:
continue
if cubes[nx, ny, nz]:
n_faces += 1
else:
queue.append((nx, ny, nz))
print(f"answer 2 is {n_faces}")