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Points within radius R.
By dreamplay, history, 9 years ago, In English

Given n points (x,y) on a euclidean plane. A radius R.
Input: Q queries of form (a,b)
Output: For each query, points within radius R

Suggest a solution to this?

Expected complexity: Better than brute force, asymptotically.

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9 years ago, # |
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Auto comment: topic has been updated by dreamplay (previous revision, new revision, compare).

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9 years ago, # |
← Rev. 3   Vote: I like it -15 Vote: I do not like it

Yeah, bad idea

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    9 years ago, # ^ |
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    For example, with very big R all our points will be located in the square (a — r, b — r, a + r, b + r) and it still brute force.

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9 years ago, # |
  Vote: I like it +7 Vote: I do not like it

Use k-d tree

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