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Two Closest Points in plane


Set of points, the points closest to each other

Given a set of points in a x and y coordinates, find the pairs of points (x1, y1) (x2, y2) that are closest.

Algorithm will be used plane sweep and data structure will be 2-4 tree.
d - minimum distance between the so-far found closest points.
p is current point.
D is the ordered set of points present in strip.
  1. Remove the points further than d to the left of p from the ordered set D that is storing the points in the strip.
  2. Determine the point on the left of p that is closest to it
  3. If the distance between this point and p is less than d (the current minimum distance), then update the closest current pair and d.

Algorithm given http://www.cs.mcgill.ca/~cs251/ClosestPair/ClosestPairPS.html
2-4 tree link is http://www.cs.mcgill.ca/~cs251/ClosestPair/2-4trees.html.

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