Faygoat's blog

By Faygoat, 11 years ago, In English

When will it be announced?

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By Faygoat, 11 years ago, In English

So I'm solving a problem that I think requires a binary search tree.

Is it possible to query for the maximum value on a key range? For example, for a node, I have the key be the "time", and the value be some arbitrary number. Is it possible to query for the maximum value where the key is on a range [a, b]? (In logarithmic time).

I googled for range trees and stuff, but those talk about reporting the points on a specified range, which is O(logN + K) where K is the number of points reported. I just want to query for a maximum value (to speed up dynamic programming).

UPDATE: Uh, the points are way too large to actually build a segment tree on it. That's why I'm using a binary search tree. (I already know I can build a seg-tree, but the points are too large, even after compression).

Thanks!

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By Faygoat, 11 years ago, In English

Hi,

I see a lot of solutions use these terms interchangeably, especially Range Tree and Segment Tree. I know how to implement a segment tree very well because I've done it multiple times in problems. However, not an interval tree or range tree. Do you need a heap like tree, or do you need a self balancing BST for it (I can't implement any at the moment. which ones should I learn)? Also, according to the wikipedia article, you can query the number of points in a 1-D, 2-D, or n-Dimensional area using a range tree, but can't you do the same thing with a 1-D, 2-D, or n-D Fenwick (Binary Indexed) Tree?

Please, someone answer me, and maybe give examples of problems solvable using a range tree?

Your help is very appreciated!!

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