35 lines
866 B
Python
Executable file
35 lines
866 B
Python
Executable file
#!/usr/bin/env python
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import itertools
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import sys
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def solve(input: str) -> int:
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def parse(input: str) -> dict[int, int]:
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return {
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depth: range
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for depth, range in (map(int, l.split(": ")) for l in input.splitlines())
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}
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def would_catch(depth: int, range: int, offset: int) -> bool:
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cycle_length = (range - 1) * 2
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return (depth + offset) % cycle_length == 0
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def compute_delay(firewall: dict[int, int]) -> int:
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for i in itertools.count():
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if any(would_catch(depth, range, i) for depth, range in firewall.items()):
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continue
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return i
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assert False # Sanity check
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firewall = parse(input)
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return compute_delay(firewall)
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def main() -> None:
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input = sys.stdin.read()
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print(solve(input))
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if __name__ == "__main__":
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main()
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