This commit is contained in:
dece 2022-01-06 20:08:52 +01:00
parent 9159c4cc72
commit 3bfb101052

59
2021/day22.py Normal file
View file

@ -0,0 +1,59 @@
with open("input22.txt") as f:
lines = [line.rstrip() for line in f]
steps = []
for line in lines:
toggle, coords = line.split()
xr, yr, zr = (
tuple(map(int, coord[2:].split("..")))
for coord in coords.split(",")
)
steps.append((toggle == "on", (xr, yr, zr)))
def print_volume(cuboids):
num_on = sum(
(x2 - x1 + 1) * (y2 - y1 + 1) * (z2 - z1 + 1)
for (x1, x2), (y1, y2), (z1, z2) in cuboids
)
print(num_on)
cuboids = []
for index, (toggle, step_cuboid) in enumerate(steps):
next_cuboids = []
(sx1, sx2), (sy1, sy2), (sz1, sz2) = step_cuboid
for cuboid in cuboids:
# If this cuboid does not intersect with our step, skip it.
if not all(
not (a1 > b2 or b1 > a2)
for (a1, a2), (b1, b2) in zip(cuboid, step_cuboid)
):
next_cuboids.append(cuboid)
continue
(cx1, cx2), (cy1, cy2), (cz1, cz2) = cuboid
# Create a new sliced cube for each intersecting plane.
# Probably cleaner to do proper cuboid intersection but pffffff
if cx1 <= sx2 <= cx2:
next_cuboids.append(((sx2 + 1, cx2), (cy1, cy2), (cz1, cz2)))
cx2 = sx2
if cx1 <= sx1 <= cx2:
next_cuboids.append(((cx1, sx1 - 1), (cy1, cy2), (cz1, cz2)))
cx1 = sx1
if cy1 <= sy2 <= cy2:
next_cuboids.append(((cx1, cx2), (sy2 + 1, cy2), (cz1, cz2)))
cy2 = sy2
if cy1 <= sy1 <= cy2:
next_cuboids.append(((cx1, cx2), (cy1, sy1 - 1), (cz1, cz2)))
cy1 = sy1
if cz1 <= sz2 <= cz2:
next_cuboids.append(((cx1, cx2), (cy1, cy2), (sz2 + 1, cz2)))
cz2 = sz2
if cz1 <= sz1 <= cz2:
next_cuboids.append(((cx1, cx2), (cy1, cy2), (cz1, sz1 - 1)))
cz1 = sz1
if toggle:
next_cuboids.append(step_cuboid)
cuboids = next_cuboids
if index == 19:
print_volume(cuboids)
print_volume(cuboids)