37 lines
995 B
Python
37 lines
995 B
Python
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#!/usr/bin/env python
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import math
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import sys
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def solve(input: list[str]) -> int:
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def parse_line(line: str) -> list[int]:
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return [int(n) for n in line.split(":")[1].split()]
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def solve(time: int, distance: int) -> int:
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# With n being the button-held-down time.
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# We want to solve: (time - n) * n > distance
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# So we want the number of intergers in ]n_1, n_2[, n_1 and n_2 roots of the quadratic
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# a = -1, b = time, c = -distance
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determinant = time**2 - 4 * distance
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if determinant <= 0:
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return 0
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max = time / 2
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delta = math.sqrt(determinant) / 2
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n_1 = max - delta
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n_2 = max + delta
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return math.ceil(n_2 - 1) - math.floor(n_1 + 1) + 1
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times, distances = map(parse_line, input)
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return math.prod(solve(t, d) for t, d in zip(times, distances))
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def main() -> None:
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input = sys.stdin.read().splitlines()
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print(solve(input))
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if __name__ == "__main__":
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main()
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