advent-of-code/2021/d22/ex2/ex2.py
Bruno BELANYI 1df896c32c treewide: fix 'ruff check' errors
This is mostly about unused imports.

A couple errors remain, but are fine in my book (using `l` as a variable
name, assigning a lambda to a variable).
2024-11-23 19:30:51 +00:00

168 lines
5.3 KiB
Python
Executable file

#!/usr/bin/env python
import functools
import itertools
import sys
from typing import List, NamedTuple, Optional, Set, Tuple
class Point(NamedTuple):
x: int
y: int
z: int
class Cuboid(NamedTuple):
min: Point
max: Point
class Step(NamedTuple):
state: bool
bounds: Cuboid
Grid = Set[Cuboid]
MAX_BOUND = 10000000000000000000000000000000000000000000 # Just a very large integer
MIN_BOUND = -MAX_BOUND
def solve(input: List[str]) -> int:
def parse() -> List[Step]:
def parse_step(line: str) -> Step:
state, cuboid = line.split(" ")
xs, ys, zs = cuboid.split(",")
min_x, max_x = map(int, xs[2:].split(".."))
min_y, max_y = map(int, ys[2:].split(".."))
min_z, max_z = map(int, zs[2:].split(".."))
# Sanity check
assert min_x <= max_x
assert min_y <= max_y
assert min_z <= max_z
bounds = Cuboid(Point(min_x, min_y, min_z), Point(max_x, max_y, max_z))
return Step(state == "on", bounds)
return [parse_step(line) for line in input]
def overlapping_range(
min_a: int, max_a: int, min_b: int, max_b: int
) -> Optional[Tuple[int, int]]:
if max_a < min_b or min_a > max_b:
return None
return max(min_a, min_b), min(max_a, max_b)
def overlapping_cube(cube: Cuboid, other: Cuboid) -> Optional[Cuboid]:
xs = overlapping_range(cube.min.x, cube.max.x, other.min.x, other.max.x)
ys = overlapping_range(cube.min.y, cube.max.y, other.min.y, other.max.y)
zs = overlapping_range(cube.min.z, cube.max.z, other.min.z, other.max.z)
if xs is None or ys is None or zs is None:
return None
return Cuboid(Point(xs[0], ys[0], zs[0]), Point(xs[1], ys[1], zs[1]))
def overlaps(cube: Cuboid, other: Cuboid) -> bool:
return overlapping_cube(cube, other) is not None
def carve_out(grid: Grid, hole: Cuboid) -> Grid:
from itertools import filterfalse
def do_carve(c: Cuboid) -> Set[Cuboid]:
cubes: Set[Cuboid] = set()
min, max = c
rightside = overlapping_range(hole.max.x + 1, MAX_BOUND, min.x, max.x)
leftside = overlapping_range(MIN_BOUND, hole.min.x - 1, min.x, max.x)
xs = overlapping_range(hole.min.x, hole.max.x, min.x, max.x)
if rightside is not None:
min_r, max_r = rightside
cubes.add(
Cuboid(Point(min_r, min.y, min.z), Point(max_r, max.y, max.z))
)
if leftside is not None:
min_l, max_l = leftside
cubes.add(
Cuboid(Point(min_l, min.y, min.z), Point(max_l, max.y, max.z))
)
backside = overlapping_range(hole.max.y + 1, MAX_BOUND, min.y, max.y)
frontside = overlapping_range(MIN_BOUND, hole.min.y - 1, min.y, max.y)
ys = overlapping_range(hole.min.y, hole.max.y, min.y, max.y)
if backside is not None and xs is not None:
min_x, max_x = xs
min_b, max_b = backside
cubes.add(
Cuboid(Point(min_x, min_b, min.z), Point(max_x, max_b, max.z))
)
if frontside is not None and xs is not None:
min_x, max_x = xs
min_f, max_f = frontside
cubes.add(
Cuboid(Point(min_x, min_f, min.z), Point(max_x, max_f, max.z))
)
topside = overlapping_range(hole.max.z + 1, MAX_BOUND, min.z, max.z)
bottomside = overlapping_range(MIN_BOUND, hole.min.z - 1, min.z, max.z)
if topside is not None and xs is not None and ys is not None:
min_x, max_x = xs
min_y, max_y = ys
min_t, max_t = topside
cubes.add(
Cuboid(Point(min_x, min_y, min_t), Point(max_x, max_y, max_t))
)
if bottomside is not None and xs is not None and ys is not None:
min_x, max_x = xs
min_y, max_y = ys
min_b, max_b = bottomside
cubes.add(
Cuboid(Point(min_x, min_y, min_b), Point(max_x, max_y, max_b))
)
return cubes
overlaps_us = lambda c: overlaps(c, hole)
of_interest, other = filter(overlaps_us, grid), filterfalse(overlaps_us, grid)
return set(other) | set(
itertools.chain.from_iterable(do_carve(c) for c in of_interest)
)
def apply(grid: Grid, step: Step) -> Grid:
cuboid = step.bounds
# Remove that cube from the grid, potentially splitting cubes that overlap
grid = carve_out(grid, cuboid)
# Add it back in if we want to turn on those cubes
if step.state:
grid.add(cuboid)
return grid
def count_cubes(c: Cuboid) -> int:
min, max = c
return (max.x + 1 - min.x) * (max.y + 1 - min.y) * (max.z + 1 - min.z)
def score(grid: Grid) -> int:
return sum(map(count_cubes, grid))
steps = parse()
grid: Grid = functools.reduce(apply, steps, set())
return score(grid)
def main() -> None:
input = [line.strip() for line in sys.stdin.readlines()]
print(solve(input))
if __name__ == "__main__":
main()