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from dataclasses import dataclass
from itertools import islice
from sys import stdin
from typing import Self, Type
@dataclass(frozen=True, slots=True)
class Pos:
x: int
y: int
z: int
def __add__(self, other: object) -> Self:
if not isinstance(other, Pos):
return NotImplemented
return self.__class__(self.x + other.x, self.y + other.y, self.z + other.z)
@classmethod
def from_str(cls: Type[Self], s: str) -> Self:
return cls(*map(int, s.split(",", maxsplit=2)))
def min_max_pos(a: Pos, b: Pos) -> tuple[Pos, Pos]:
minx, maxx = min(a.x, b.x), max(a.x, b.x)
miny, maxy = min(a.y, b.y), max(a.y, b.y)
minz, maxz = min(a.z, b.z), max(a.z, b.z)
return Pos(minx, miny, minz), Pos(maxx, maxy, maxz)
@dataclass(frozen=True, slots=True)
class Brick:
a: Pos
b: Pos
def xy_overlaps(self, other: Self) -> bool:
return (
self.a.x <= other.b.x
and self.b.x >= other.a.x
and self.a.y <= other.b.y
and self.b.y >= other.a.y
)
def collides(self, other: Self) -> bool:
return (
self.xy_overlaps(other) and self.a.z <= other.b.z and self.b.z >= other.a.z
)
def __add__(self, other: object) -> Self:
if not isinstance(other, Pos):
return NotImplemented
return self.__class__(self.a + other, self.b + other)
@classmethod
def from_str(cls, s: str):
return Brick(*min_max_pos(*map(Pos.from_str, s.split("~", maxsplit=1))))
inp = [Brick.from_str(line.rstrip("\n")) for line in stdin]
def simulate(inp: list[Brick]) -> int:
motion = True
fallen = set()
inp.sort(key=lambda b: b.a.z)
while motion:
motion = False
for i, b in enumerate(inp):
if b.a.z <= 1:
continue
max_dz = b.a.z - 1
for other in islice(inp, 0, i):
if not other.xy_overlaps(b):
continue
for dz in range(
max(b.a.z - other.b.z, 1),
min(max(b.a.z - other.a.z, 0), max_dz) + 1,
):
if other.collides(b + Pos(0, 0, -dz)):
max_dz = dz - 1
break
if max_dz == 0:
break
if max_dz == 0:
continue
fallen.add(i)
inp[i] = b + Pos(0, 0, -max_dz)
motion = True
return len(fallen)
simulate(inp)
print("settled")
p1 = p2 = 0
for i, _ in enumerate(inp):
copy = inp.copy()
copy.pop(i)
fallen = simulate(copy)
if fallen == 0:
p1 += 1
else:
p2 += fallen
print(f"{i} / {len(inp)}")
print(p1)
print(p2)
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