advent-of-code/2019-python/output/day_10.py

96 lines
2.2 KiB
Python

from collections import OrderedDict, defaultdict, deque
from math import atan2
from output import answer
n = 10
title = "Monitoring Station"
@answer(1, "The monitor station will see {} asteroids at best")
def part_1(o):
return o[0]
@answer(
2,
"The asteroid at y=3 x=17 (checksum {}) will be the 200th lazer vapored asteroid, making some elf happy",
)
def part_2(o):
return o[1]
def solve(data):
matrix = data.strip().split()
pos, visible = _map_visible_asteroids(matrix)
p1 = len(set(dict(visible).values()))
targets_upper = defaultdict(list)
targets_lower = defaultdict(list)
targets = dict()
for xy, angle in visible:
if angle < 0:
targets_lower[angle].append(xy)
else:
targets_upper[angle].append(xy)
for k, v in OrderedDict(
sorted(targets_upper.items(), key=lambda x: x[0], reverse=True)
+ sorted(targets_lower.items(), key=lambda x: x[0], reverse=True)
).items():
targets[k] = deque(
sorted(
v,
key=lambda xy: sum(abs(pos[i] - xy[i]) for i in range(2)),
)
)
vapored = 0
x = 0
y = 0
while vapored < 200:
popped = False
for tk in targets.keys():
if targets[tk]:
x, y = targets[tk].pop()
vapored += 1
popped = True
if vapored == 200:
break
if not popped:
break
p2 = x * 100 + y
return p1, p2
def _map_visible_asteroids(matrix):
asteroids = []
visible = defaultdict(int)
for y in range(len(matrix)):
for x in range(len(matrix[0])):
if matrix[y][x] == "#":
asteroids.append((x, y))
for a, b in asteroids:
visible[(a, b)] = [
((x, y), atan2(x - a, y - b)) for x, y in asteroids if (a, b) != (x, y)
]
return max(visible.items(), key=lambda x: len(set(dict(x[1]).values())))
if __name__ == "__main__":
with open("./input/10.txt", "r") as f:
inp = f.read().strip()
inp = solve(inp)
a = part_1(inp)
b = part_2(inp)
assert a == 292
assert b == 317