|
- rows = open(0).read().splitlines()
- grid = {complex(x, y) for y, l in enumerate(rows)
- for x, c in enumerate(l) if c in '#'}
- dir8 = {dx + dy for dx in [-1, 0, 1]
- for dy in [-1j, 0, 1j] if not dx + dy == 0}
- dir3 = [(k, {k, k + k * 1j, k - k * 1j}) for k in [-1j, 1j, -1, 1]]
-
-
- def render(grid):
- xmin, *_, xmax = sorted(int(p.real) for p in grid)
- ymin, *_, ymax = sorted(int(p.imag) for p in grid)
- sab = ''
- for y in range(ymin, ymax + 1):
- for x in range(xmin, xmax + 1):
- sab += grid.get(complex(x, y), ' ')
- sab += '\n'
- return sab
-
-
- def look(p):
- for k, ds in dir3:
- if not {p + d for d in ds} & grid:
- return p + k
-
-
- for i in range(1, 100000):
-
- moves = {}
- for p in grid:
- if not any(p + dp in grid for dp in dir8):
- continue
- moves.setdefault(look(p), []).append(p)
- dir3 = dir3[1:] + dir3[:1]
-
- if not moves:
- print(i)
- break
-
- for k, vs in moves.items():
- if k is not None:
- if len(vs) == 1:
- grid = grid - set(vs) | {k}
-
- if i == 10:
- print(render({k: '#' for k in grid}).count(' '))
|
