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Add day 16

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Sijmen 2023-12-29 23:39:23 +01:00
parent 14354c85b8
commit 89e2c58a78
1 changed files with 76 additions and 0 deletions
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day16.py Normal file
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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()