lemon/random.cc
author Peter Kovacs <kpeter@inf.elte.hu>
Thu, 06 Aug 2009 20:12:43 +0200
changeset 760 83ce7ce39f21
parent 209 765619b7cbb2
permissions -rw-r--r--
Rework and fix the implementation of MinMeanCycle (#179)

- Fix the handling of the cycle means.
- Many implementation improvements:
- More efficient data storage for the strongly connected
components.
- Better handling of BFS queues.
- Merge consecutive BFS searches (perform two BFS searches
instead of three).

This version is about two times faster on average and an order of
magnitude faster if there are a lot of strongly connected components.
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/* -*- mode: C++; indent-tabs-mode: nil; -*-
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 *
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 * This file is a part of LEMON, a generic C++ optimization library.
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 *
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 * Copyright (C) 2003-2009
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 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
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 * (Egervary Research Group on Combinatorial Optimization, EGRES).
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 *
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 * Permission to use, modify and distribute this software is granted
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 * provided that this copyright notice appears in all copies. For
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 * precise terms see the accompanying LICENSE file.
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 *
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 * This software is provided "AS IS" with no warranty of any kind,
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 * express or implied, and with no claim as to its suitability for any
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 * purpose.
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 *
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 */
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///\file
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///\brief Instantiation of the Random class.
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#include <lemon/random.h>
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namespace lemon {
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  /// \brief Global random number generator instance
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  ///
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  /// A global Mersenne Twister random number generator instance.
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  Random rnd;
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}