AALG7: Building Kd-trees and range trees: presorting

[@derarcane]

Thanks. I enjoyed the explanation using the pseudocode, though I'd also like to see the how time complexity of the recurrence relation is calculated.

[@doekewartena5729]

For people trying to implement this, be aware of the following:
Let's say you have a set of points where the median in x is 80 for example, but you have multiple points where x is 80.
Now on this line: if Y[i].x

[@mingjunzhang]

Good one, thank you for the work.

[@richardliu7848]

Thank you, thank you!

[@a.g-z4x]

Thank you very much.