40 lines
871 B
Python
40 lines
871 B
Python
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from math import sqrt
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def distance(p1, p2) -> float:
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return (p1[0] - p2[0]) ** 2 + (p1[1] - p2[1]) ** 2
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def points(k: int):
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s = 290797
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mod = 50515093
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# s = 5
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# mod = 23
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points = []
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for _ in range(k):
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sn = (s ** 2) % mod
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p = (s, sn)
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points.append(p)
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s = (sn ** 2) % mod
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return points
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def euler_816():
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ps = sorted(points(2000000), key=lambda p: p[0])
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d_min = float("inf")
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sweep_dist = 5 # heuristic
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for i in range(len(ps)):
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for j in range(i, min(i + sweep_dist, len(ps))):
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if i == j:
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continue
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d = distance(ps[i], ps[j])
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if d < d_min:
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d_min = d
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return round(sqrt(d_min), 9)
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if __name__ == "__main__":
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solution = euler_816()
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print("e816.py: " + str(solution))
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assert(solution == 20.880613018)
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