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HARD PROBLEM FOR ME
By Kenneth-nlogn, 10 years ago, In English

Hello, I recently started studying algorithms in computational geometry, I seem to have problems with the following computational geometry problem, I have searched long and hard but still cant find a solution: it goes: given n points, find the triplicate whose angle is close to 90 as possible. any suggestions will be appreciated.

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10 years ago, # |
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Maximal N is ?

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    10 years ago, # ^ |
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    MAX N = 100000

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      10 years ago, # ^ |
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      An algorithm may work for n ≤ 1000, algorithm. define S as the set contains n given point.

      for p1 in S:
    for p2 in S - {p1}:
        a[i] = Angle(p2p1, Ox)
    using 2 pointers to get the angles whose sum is closest to 90 degree

      After some searching, I found a similar question here

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