Anders Englöf Ytterström
044df24990
For p1 a BFS algorithm is fast enough. For pt 2, for the third day in a row, it did not work. I caved in and used recursion and memoisation for DFS instead, instantly fast as lightning. I finished by making the pt 2 code compatible with pt 1.
33 lines
747 B
Python
33 lines
747 B
Python
import functools
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from collections import defaultdict
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def solve(data):
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G = defaultdict(set)
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for line in data.splitlines():
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f, *t = line.split()
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G[f[:-1]] = set(t)
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@functools.cache
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def _traverse(k, fasttrack=True, fft=False, dac=False):
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if k == "out":
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return fasttrack or (fft and dac)
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return sum(
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_traverse(nk, fasttrack, fft or k == "fft", dac or k == "dac")
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for nk in G[k]
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)
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return _traverse("you"), _traverse("svr", fasttrack=False)
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if __name__ == "__main__":
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with open("./input/11.txt", "r") as f:
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inp = f.read().strip()
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p1, p2 = solve(inp)
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print(p1)
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print(p2)
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assert p1 == 649
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assert p2 == 458948453421420
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