def part_a(data):
seen = set()
grid = ZGrid(data)
while True:
k = tuple(grid.items())
if k in seen:
return sum(2**i for i, glyph in enumerate(grid.values())
if glyph == "#")
seen.add(k)
evolve_a(grid)
def __init__(self, data, part="a"):
grid = ZGrid(data, on=".", off="#")
if part == "b":
[z0] = [z for z, v in grid.items() if v == "@"]
pos = ("@0", "@1", "@2", "@3")
for dz in [0, -1j, 1, 1j, -1]:
grid[z0 + dz] = grid.off
for p, dz in zip(pos, [-1 - 1j, 1 - 1j, 1 + 1j, -1 + 1j]):
grid[z0 + dz] = p
else:
pos = ("@", )
graph = grid.graph(extra=frozenset(string.ascii_letters).union(pos))
self.all_keys = {k for k in graph.extra if k in string.ascii_lowercase}
# map of the other keys that must be acquired before each key is acquired
self.obstructions = {k: set() for k in self.all_keys}
# precached distances between points of interest
self.kdist = {}
for k0 in self.all_keys:
for p in pos:
try:
path = nx.shortest_path(graph, graph.extra[p],
graph.extra[k0])
except nx.NetworkXNoPath:
pass
else:
break
else:
raise Exception
self.kdist[k0, p] = self.kdist[p, k0] = len(path) - 1
assert path[0] == graph.extra[p]
assert path[-1] == graph.extra[k0]
for p in path[1:-1]:
if p in graph.extra.values():
k1 = grid[p].lower()
self.obstructions[k0].add(k1)
for k1, k2 in combinations(self.all_keys, 2):
z1 = graph.extra[k1]
z2 = graph.extra[k2]
try:
d = nx.shortest_path_length(graph, z1, z2)
except nx.NetworkXNoPath:
continue
self.kdist[k1, k2] = self.kdist[k2, k1] = d
state0 = pos, frozenset()
AStar.__init__(self, state0, target=None)
#####.#.###.#######.#######.###.###.#.#.#
#.......#.......#.#.#.#.#...#...#...#.#.#
#####.###.#####.#.#.#.#.###.###.#.###.###
#.......#.....#.#...#...............#...#
#############.#.#.###.###################
A O F N
A A D M """
grid = ZGrid(data, on=".", off="#")
h, w = np.array(grid).shape
dzs = [-1j, 1, 1j, -1]
# parse the warps
outside = {}
inside = {}
for z, glyph in grid.items():
if glyph in string.ascii_uppercase:
for dz in dzs:
if grid.get(z + dz) == ".":
zp = z + dz # actual position of portal
name = glyph + grid.get(z - dz) # add other letter
if 3 < z.real < w - 3 and 3 < z.imag < h - 3:
side = inside
else:
side = outside
if zp - z in {1j, 1}:
name = name[::-1] # reverse the label
side[name] = zp
break
state0 = outside.pop("AA")