Path: csiph.com!usenet.pasdenom.info!news.albasani.net!newsfeed.freenet.ag!news2.euro.net!newsgate.cistron.nl!newsgate.news.xs4all.nl!post.news.xs4all.nl!not-for-mail
Return-Path: <python-python-list@m.gmane.org>
X-Original-To: python-list@python.org
Delivered-To: python-list@mail.python.org
X-Spam-Status: OK 0.001
X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'algorithm': 0.03; 'binary': 0.05; 'python': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'visited': 0.09; 'dfs': 0.16; 'dictionaries': 0.16; 'from:addr:behnel.de': 0.16; 'from:addr:stefan_ml': 0.16; 'from:name:stefan behnel': 0.16; 'hashable': 0.16; 'message-id:@dough.gmane.org': 0.16; 'received:80.91.229.3': 0.16; 'received:mnet-online.de': 0.16; 'received:plane.gmane.org': 0.16; 'solver': 0.16; 'stefan': 0.17; 'header:In-Reply-To:1': 0.25; 'header:User-Agent:1': 0.26; 'tree': 0.27; 'header:X-Complaints-To:1': 0.28; 'record': 0.28; 'depth': 0.29; 'dictionary': 0.29; 'lists': 0.31; 'url:python': 0.32; 'structure': 0.32; 'could': 0.32; 'ordered': 0.33; 'right?': 0.33; 'subject:data': 0.33; 'to:addr:python-list': 0.33; 'built-in': 0.35; 'there': 0.35; 'received:org': 0.36; 'url:org': 0.36; 'totally': 0.36; 'url:library': 0.36; 'does': 0.37; 'data': 0.37; 'subject:: ': 0.38; 'perform': 0.38; 'url:docs': 0.38; 'to:addr:python.org': 0.39; 'header:Received:5': 0.40; 'help': 0.40; 'first': 0.61; 'received:93': 0.72; 'bst': 0.84; 'subject:Best': 0.91
X-Injected-Via-Gmane: http://gmane.org/
To: python-list@python.org
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
References: <CACA+676A=G=3+wvaHw3H0LAo2cghztXo4+9ORR73CXBOOpW0ZQ@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
X-Gmane-NNTP-Posting-Host: ppp-93-104-1-135.dynamic.mnet-online.de
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120430 Thunderbird/12.0.1
In-Reply-To: <CACA+676A=G=3+wvaHw3H0LAo2cghztXo4+9ORR73CXBOOpW0ZQ@mail.gmail.com>
X-BeenThere: python-list@python.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: General discussion list for the Python programming language <python-list.python.org>
List-Unsubscribe: <http://mail.python.org/mailman/options/python-list>, <mailto:python-list-request@python.org?subject=unsubscribe>
List-Archive: <http://mail.python.org/pipermail/python-list>
List-Post: <mailto:python-list@python.org>
List-Help: <mailto:python-list-request@python.org?subject=help>
List-Subscribe: <http://mail.python.org/mailman/listinfo/python-list>, <mailto:python-list-request@python.org?subject=subscribe>
Newsgroups: comp.lang.python
Message-ID: <mailman.1738.1341314657.4697.python-list@python.org>
Lines: 24
NNTP-Posting-Host: 2001:888:2000:d::a6
X-Trace: 1341314657 news.xs4all.nl 6848 [2001:888:2000:d::a6]:43453
X-Complaints-To: abuse@xs4all.nl
Xref: csiph.com comp.lang.python:24812

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