Files
adventofcode/2024/src/aoc/days/day12.py
2024-12-12 22:18:32 +01:00

102 lines
3.1 KiB
Python

import numpy
from . import CombinedRunner
DIRECTIONS = [
(-1, 0),
(1, 0),
(0, -1),
(0, 1),
]
class DayRunner(CombinedRunner):
@classmethod
def run_both(cls, input: str) -> tuple[int, int]:
grid = numpy.array(list(map(list, input.strip().split("\n"))))
score = 0
score2 = 0
for y in range(grid.shape[0]):
for x in range(grid.shape[1]):
if grid[y, x] == ".":
continue
search = grid[y, x]
grid[y, x] = "."
todo = [(y, x)]
cluster = {(y, x)}
def enqueue(y, x):
if grid[y, x] == search:
grid[y, x] = "."
todo.append((y, x))
cluster.add((y, x))
while todo:
cy, cx = todo.pop()
if cx > 0:
enqueue(cy, cx - 1)
if cy > 0:
enqueue(cy - 1, cx)
if cx < grid.shape[1] - 1:
enqueue(cy, cx + 1)
if cy < grid.shape[0] - 1:
enqueue(cy + 1, cx)
side_length = sum(
sum((cy + dy, cx + dx) not in cluster for dy, dx in DIRECTIONS)
for cy, cx in cluster
)
corners = 0
for cy, cx in cluster:
# Outer corners
corners += (cy, cx - 1) not in cluster and (
cy - 1,
cx,
) not in cluster
corners += (cy, cx + 1) not in cluster and (
cy - 1,
cx,
) not in cluster
corners += (cy, cx - 1) not in cluster and (
cy + 1,
cx,
) not in cluster
corners += (cy, cx + 1) not in cluster and (
cy + 1,
cx,
) not in cluster
# Inner corners
corners += (
(cy, cx - 1) in cluster
and (cy - 1, cx) in cluster
and (cy - 1, cx - 1) not in cluster
)
corners += (
(cy, cx + 1) in cluster
and (cy - 1, cx) in cluster
and (cy - 1, cx + 1) not in cluster
)
corners += (
(cy, cx - 1) in cluster
and (cy + 1, cx) in cluster
and (cy + 1, cx - 1) not in cluster
)
corners += (
(cy, cx + 1) in cluster
and (cy + 1, cx) in cluster
and (cy + 1, cx + 1) not in cluster
)
score += side_length * len(cluster)
score2 += corners * len(cluster)
return (score, score2)