78 lines
2.1 KiB
Python
78 lines
2.1 KiB
Python
|
#!/usr/bin/env python
|
||
|
|
|
||
|
|
|
||
|
|
import re
|
||
|
|
import sys
|
||
|
|
from copy import deepcopy
|
||
|
|
from dataclasses import dataclass
|
||
|
|
from math import gcd
|
||
|
|
from typing import List
|
||
|
|
|
||
|
|
|
||
|
|
@dataclass
|
||
|
|
class Position:
|
||
|
|
x: int
|
||
|
|
y: int
|
||
|
|
z: int
|
||
|
|
|
||
|
|
|
||
|
|
def line_to_pos(l: str) -> Position:
|
||
|
|
"<x=4, y=1, z=1>"
|
||
|
|
regex = r"<x=(?P<x>[^,]*), y=(?P<y>[^,]*), z=(?P<z>[^,]*)>"
|
||
|
|
match = re.search(regex, l)
|
||
|
|
assert match is not None # Sanity check
|
||
|
|
return Position(*(int(match.group(g)) for g in ("x", "y", "z")))
|
||
|
|
|
||
|
|
|
||
|
|
def lcm(a: int, b: int, c: int) -> int:
|
||
|
|
def lcm_2(a: int, b: int) -> int:
|
||
|
|
return abs(a * b) // gcd(a, b)
|
||
|
|
|
||
|
|
return lcm_2(lcm_2(a, b), c)
|
||
|
|
|
||
|
|
|
||
|
|
def main() -> None:
|
||
|
|
asteroids = [line_to_pos(line) for line in sys.stdin.readlines()]
|
||
|
|
velocities = [Position(0, 0, 0) for __ in asteroids]
|
||
|
|
|
||
|
|
cycles: List[int] = []
|
||
|
|
for attr in ("x", "y", "z"):
|
||
|
|
all_prev_pos = [deepcopy(asteroids)]
|
||
|
|
all_prev_vel = [deepcopy(velocities)]
|
||
|
|
i = 0
|
||
|
|
|
||
|
|
found = False
|
||
|
|
while not found:
|
||
|
|
i += 1
|
||
|
|
for orig, v in zip(asteroids, velocities):
|
||
|
|
for other in asteroids:
|
||
|
|
if orig.x != other.x:
|
||
|
|
v.x += 1 if orig.x < other.x else -1
|
||
|
|
if orig.y != other.y:
|
||
|
|
v.y += 1 if orig.y < other.y else -1
|
||
|
|
if orig.z != other.z:
|
||
|
|
v.z += 1 if orig.z < other.z else -1
|
||
|
|
|
||
|
|
for asteroid, v in zip(asteroids, velocities):
|
||
|
|
asteroid.x += v.x
|
||
|
|
asteroid.y += v.y
|
||
|
|
asteroid.z += v.z
|
||
|
|
|
||
|
|
for old_pos, old_vel in zip(all_prev_pos, all_prev_vel):
|
||
|
|
if all(
|
||
|
|
n.__getattribute__(attr) == o.__getattribute__(attr)
|
||
|
|
for n, o in zip(asteroids, old_pos)
|
||
|
|
) and all(
|
||
|
|
n.__getattribute__(attr) == o.__getattribute__(attr)
|
||
|
|
for n, o in zip(velocities, old_vel)
|
||
|
|
):
|
||
|
|
found = True
|
||
|
|
|
||
|
|
cycles.append(i)
|
||
|
|
|
||
|
|
print(lcm(*cycles))
|
||
|
|
|
||
|
|
|
||
|
|
if __name__ == "__main__":
|
||
|
|
main()
|