77 lines
2.3 KiB
Python
77 lines
2.3 KiB
Python
|
import sys
|
||
|
|
|
||
|
|
def simulate(map, entry):
|
||
|
|
seen = set()
|
||
|
|
energised = set()
|
||
|
|
stack: list[tuple[tuple[int, int], tuple[int, int]]] = [entry]
|
||
|
|
while stack:
|
||
|
|
entry = stack.pop()
|
||
|
|
if entry in seen:
|
||
|
|
continue
|
||
|
|
seen.add(entry)
|
||
|
|
|
||
|
|
((x, y), (dx, dy)) = entry
|
||
|
|
if not (0 <= y < len(map)) or not (0 <= x < len(map[y])):
|
||
|
|
continue
|
||
|
|
|
||
|
|
energised.add((x, y))
|
||
|
|
|
||
|
|
match map[y][x]:
|
||
|
|
case ".":
|
||
|
|
stack.append(((x + dx, y + dy), (dx, dy)))
|
||
|
|
case "-" if dy == 0:
|
||
|
|
stack.append(((x + dx, y + dy), (dx, dy)))
|
||
|
|
case "-":
|
||
|
|
stack.append(((x - 1, y), (-1, 0)))
|
||
|
|
stack.append(((x + 1, y), (1, 0)))
|
||
|
|
case "|" if dx == 0:
|
||
|
|
stack.append(((x + dx, y + dy), (dx, dy)))
|
||
|
|
case "|":
|
||
|
|
stack.append(((x, y - 1), (0, -1)))
|
||
|
|
stack.append(((x, y + 1), (0, 1)))
|
||
|
|
case "/" if (dx, dy) == (1, 0):
|
||
|
|
stack.append(((x, y - 1), (0, -1)))
|
||
|
|
case "/" if (dx, dy) == (-1, 0):
|
||
|
|
stack.append(((x, y + 1), (0, 1)))
|
||
|
|
case "/" if (dx, dy) == (0, 1):
|
||
|
|
stack.append(((x - 1, y), (-1, 0)))
|
||
|
|
case "/" if (dx, dy) == (0, -1):
|
||
|
|
stack.append(((x + 1, y), (1, 0)))
|
||
|
|
case "\\" if (dx, dy) == (1, 0):
|
||
|
|
stack.append(((x, y + 1), (0, 1)))
|
||
|
|
case "\\" if (dx, dy) == (-1, 0):
|
||
|
|
stack.append(((x, y - 1), (0, -1)))
|
||
|
|
case "\\" if (dx, dy) == (0, 1):
|
||
|
|
stack.append(((x + 1, y), (1, 0)))
|
||
|
|
case "\\" if (dx, dy) == (0, -1):
|
||
|
|
stack.append(((x - 1, y), (-1, 0)))
|
||
|
|
|
||
|
|
return len(energised)
|
||
|
|
|
||
|
|
def main():
|
||
|
|
with open(sys.argv[1]) as f:
|
||
|
|
map = [list(l) for l in f.read().strip().splitlines()]
|
||
|
|
|
||
|
|
part1 = simulate(map, ((0, 0), (1, 0)))
|
||
|
|
|
||
|
|
part2 = 0
|
||
|
|
for y in range(len(map)):
|
||
|
|
w = len(map[y])
|
||
|
|
|
||
|
|
xp = simulate(map, ((0, y), (1, 0)))
|
||
|
|
xm = simulate(map, ((w - 1, y), (-1, 0)))
|
||
|
|
part2 = max(part2, xp, xm)
|
||
|
|
|
||
|
|
for x in range(len(map)):
|
||
|
|
h = len(map)
|
||
|
|
|
||
|
|
yp = simulate(map, ((x, 0), (0, 1)))
|
||
|
|
ym = simulate(map, ((x, h - 1), (0, -1)))
|
||
|
|
part2 = max(part2, yp, ym)
|
||
|
|
|
||
|
|
print(part1, part2)
|
||
|
|
|
||
|
|
|
||
|
|
if __name__ == "__main__":
|
||
|
|
main()
|