Re: Best data structure for DFS on large graphs

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From	Stefan Behnel <stefan_ml@behnel.de>
Subject	Re: Best data structure for DFS on large graphs
Date	Tue, 03 Jul 2012 13:23:58 +0200
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Miheer Dewaskar, 03.07.2012 13:11:
> I want to make a combinatorial game solver in python.The algorithm is to
> perform Depth First Search (DFS) on the states of the game.
> For DFS I,would need to keep a record of the visited states.What is the
> best data structure for it,keeping in mind that the number of states could
> be large?
> 
> I was thinking about using Dictionary or a Binary Search Tree (BST)
> ,assuming that the states can be made hashable and totally ordered
> respectively.
> I am not sure,but if there are large number of states Dictionaries wont
> help much right?

Dicts are fast for lookup, not for searching.


> Anyway, does python have a built-in BST like data-structure ?

It has lists and bisect:

http://docs.python.org/library/bisect.html

Stefan

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Re: Best data structure for DFS on large graphs Stefan Behnel <stefan_ml@behnel.de> - 2012-07-03 13:23 +0200

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