33 lines
845 B
Python
33 lines
845 B
Python
from lib import *
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input = read_input(2021, 20)
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lines = input.splitlines()
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def solve(n):
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algo = [c == "#" for c in lines[0]]
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grid = {(j, i) for i, line in enumerate(lines[2:]) for j, x in enumerate(line) if x == "#"}
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inf = False
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for _ in range(n):
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new_inf = inf != algo[0]
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candidates = {(p, q) for x, y in grid for p, q in get_neighbors(x, y, diag=True, include_self=True)}
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new_grid = set()
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for x, y in candidates:
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idx = 0
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for p, q in sorted(get_neighbors(x, y, diag=True, include_self=True), key=lambda a: a[::-1]):
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idx <<= 1
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idx |= ((p, q) in grid) != inf
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if algo[idx] != new_inf:
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new_grid.add((x, y))
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grid = new_grid
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inf = new_inf
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return len(grid)
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print(solve(2))
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print(solve(50))
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