lemon/concepts/digraph.h
author Alpar Juttner <alpar@cs.elte.hu>
Wed, 12 Sep 2012 17:25:48 +0200
changeset 995 4bb9e72e1a41
parent 786 e20173729589
child 1049 7bf489cf624e
child 1084 8b2d4e5d96e4
permissions -rw-r--r--
Bugfix in adaptor_test.cc (#448)
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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) 2003-2010
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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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#ifndef LEMON_CONCEPTS_DIGRAPH_H
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#define LEMON_CONCEPTS_DIGRAPH_H
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///\ingroup graph_concepts
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///\file
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///\brief The concept of directed graphs.
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#include <lemon/core.h>
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#include <lemon/concepts/maps.h>
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#include <lemon/concept_check.h>
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#include <lemon/concepts/graph_components.h>
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namespace lemon {
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  namespace concepts {
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    /// \ingroup graph_concepts
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    ///
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    /// \brief Class describing the concept of directed graphs.
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    ///
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    /// This class describes the common interface of all directed
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    /// graphs (digraphs).
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    ///
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    /// Like all concept classes, it only provides an interface
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    /// without any sensible implementation. So any general algorithm for
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    /// directed graphs should compile with this class, but it will not
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    /// run properly, of course.
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    /// An actual digraph implementation like \ref ListDigraph or
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    /// \ref SmartDigraph may have additional functionality.
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    ///
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    /// \sa Graph
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    class Digraph {
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    private:
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      /// Diraphs are \e not copy constructible. Use DigraphCopy instead.
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      Digraph(const Digraph &) {}
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      /// \brief Assignment of a digraph to another one is \e not allowed.
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      /// Use DigraphCopy instead.
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      void operator=(const Digraph &) {}
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    public:
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      /// Default constructor.
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      Digraph() { }
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      /// The node type of the digraph
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      /// This class identifies a node of the digraph. It also serves
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      /// as a base class of the node iterators,
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      /// thus they convert to this type.
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      class Node {
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      public:
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        /// Default constructor
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        /// Default constructor.
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        /// \warning It sets the object to an undefined value.
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        Node() { }
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        /// Copy constructor.
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        /// Copy constructor.
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        ///
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        Node(const Node&) { }
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        /// %Invalid constructor \& conversion.
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        /// Initializes the object to be invalid.
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        /// \sa Invalid for more details.
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        Node(Invalid) { }
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        /// Equality operator
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        /// Equality operator.
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        ///
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        /// Two iterators are equal if and only if they point to the
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        /// same object or both are \c INVALID.
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        bool operator==(Node) const { return true; }
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        /// Inequality operator
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        /// Inequality operator.
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        bool operator!=(Node) const { return true; }
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        /// Artificial ordering operator.
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        /// Artificial ordering operator.
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        ///
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        /// \note This operator only has to define some strict ordering of
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        /// the nodes; this order has nothing to do with the iteration
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        /// ordering of the nodes.
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        bool operator<(Node) const { return false; }
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      };
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      /// Iterator class for the nodes.
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      /// This iterator goes through each node of the digraph.
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      /// Its usage is quite simple, for example, you can count the number
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      /// of nodes in a digraph \c g of type \c %Digraph like this:
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      ///\code
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      /// int count=0;
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      /// for (Digraph::NodeIt n(g); n!=INVALID; ++n) ++count;
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      ///\endcode
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      class NodeIt : public Node {
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      public:
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        /// Default constructor
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        /// Default constructor.
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        /// \warning It sets the iterator to an undefined value.
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        NodeIt() { }
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        /// Copy constructor.
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        /// Copy constructor.
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        ///
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        NodeIt(const NodeIt& n) : Node(n) { }
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        /// %Invalid constructor \& conversion.
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        /// Initializes the iterator to be invalid.
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        /// \sa Invalid for more details.
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        NodeIt(Invalid) { }
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        /// Sets the iterator to the first node.
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        /// Sets the iterator to the first node of the given digraph.
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        ///
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        explicit NodeIt(const Digraph&) { }
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        /// Sets the iterator to the given node.
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        /// Sets the iterator to the given node of the given digraph.
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        ///
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        NodeIt(const Digraph&, const Node&) { }
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        /// Next node.
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        /// Assign the iterator to the next node.
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        ///
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        NodeIt& operator++() { return *this; }
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      };
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      /// The arc type of the digraph
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      /// This class identifies an arc of the digraph. It also serves
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      /// as a base class of the arc iterators,
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      /// thus they will convert to this type.
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      class Arc {
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      public:
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        /// Default constructor
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        /// Default constructor.
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        /// \warning It sets the object to an undefined value.
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        Arc() { }
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        /// Copy constructor.
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        /// Copy constructor.
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        ///
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        Arc(const Arc&) { }
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        /// %Invalid constructor \& conversion.
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        /// Initializes the object to be invalid.
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        /// \sa Invalid for more details.
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        Arc(Invalid) { }
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        /// Equality operator
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        /// Equality operator.
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        ///
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        /// Two iterators are equal if and only if they point to the
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        /// same object or both are \c INVALID.
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        bool operator==(Arc) const { return true; }
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        /// Inequality operator
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        /// Inequality operator.
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        bool operator!=(Arc) const { return true; }
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        /// Artificial ordering operator.
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        /// Artificial ordering operator.
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        ///
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        /// \note This operator only has to define some strict ordering of
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        /// the arcs; this order has nothing to do with the iteration
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        /// ordering of the arcs.
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        bool operator<(Arc) const { return false; }
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      };
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      /// Iterator class for the outgoing arcs of a node.
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      /// This iterator goes trough the \e outgoing arcs of a certain node
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      /// of a digraph.
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      /// Its usage is quite simple, for example, you can count the number
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      /// of outgoing arcs of a node \c n
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      /// in a digraph \c g of type \c %Digraph as follows.
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      ///\code
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      /// int count=0;
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      /// for (Digraph::OutArcIt a(g, n); a!=INVALID; ++a) ++count;
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      ///\endcode
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      class OutArcIt : public Arc {
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      public:
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        /// Default constructor
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        /// Default constructor.
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        /// \warning It sets the iterator to an undefined value.
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        OutArcIt() { }
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        /// Copy constructor.
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        /// Copy constructor.
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        ///
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        OutArcIt(const OutArcIt& e) : Arc(e) { }
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        /// %Invalid constructor \& conversion.
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        /// Initializes the iterator to be invalid.
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        /// \sa Invalid for more details.
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        OutArcIt(Invalid) { }
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        /// Sets the iterator to the first outgoing arc.
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        /// Sets the iterator to the first outgoing arc of the given node.
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        ///
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        OutArcIt(const Digraph&, const Node&) { }
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        /// Sets the iterator to the given arc.
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        /// Sets the iterator to the given arc of the given digraph.
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        ///
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        OutArcIt(const Digraph&, const Arc&) { }
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        /// Next outgoing arc
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        /// Assign the iterator to the next
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        /// outgoing arc of the corresponding node.
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        OutArcIt& operator++() { return *this; }
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      };
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      /// Iterator class for the incoming arcs of a node.
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      /// This iterator goes trough the \e incoming arcs of a certain node
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      /// of a digraph.
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      /// Its usage is quite simple, for example, you can count the number
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      /// of incoming arcs of a node \c n
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      /// in a digraph \c g of type \c %Digraph as follows.
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      ///\code
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      /// int count=0;
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      /// for(Digraph::InArcIt a(g, n); a!=INVALID; ++a) ++count;
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      ///\endcode
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      class InArcIt : public Arc {
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      public:
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        /// Default constructor
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        /// Default constructor.
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        /// \warning It sets the iterator to an undefined value.
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        InArcIt() { }
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        /// Copy constructor.
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        /// Copy constructor.
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        ///
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        InArcIt(const InArcIt& e) : Arc(e) { }
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        /// %Invalid constructor \& conversion.
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        /// Initializes the iterator to be invalid.
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        /// \sa Invalid for more details.
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        InArcIt(Invalid) { }
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        /// Sets the iterator to the first incoming arc.
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        /// Sets the iterator to the first incoming arc of the given node.
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        ///
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        InArcIt(const Digraph&, const Node&) { }
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        /// Sets the iterator to the given arc.
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        /// Sets the iterator to the given arc of the given digraph.
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        ///
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        InArcIt(const Digraph&, const Arc&) { }
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        /// Next incoming arc
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        /// Assign the iterator to the next
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        /// incoming arc of the corresponding node.
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        InArcIt& operator++() { return *this; }
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      };
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      /// Iterator class for the arcs.
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      /// This iterator goes through each arc of the digraph.
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      /// Its usage is quite simple, for example, you can count the number
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      /// of arcs in a digraph \c g of type \c %Digraph as follows:
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      ///\code
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      /// int count=0;
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      /// for(Digraph::ArcIt a(g); a!=INVALID; ++a) ++count;
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      ///\endcode
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      class ArcIt : public Arc {
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      public:
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        /// Default constructor
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        /// Default constructor.
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        /// \warning It sets the iterator to an undefined value.
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        ArcIt() { }
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        /// Copy constructor.
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        /// Copy constructor.
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        ///
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        ArcIt(const ArcIt& e) : Arc(e) { }
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        /// %Invalid constructor \& conversion.
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        /// Initializes the iterator to be invalid.
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        /// \sa Invalid for more details.
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        ArcIt(Invalid) { }
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        /// Sets the iterator to the first arc.
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        /// Sets the iterator to the first arc of the given digraph.
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        ///
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        explicit ArcIt(const Digraph& g) { ignore_unused_variable_warning(g); }
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        /// Sets the iterator to the given arc.
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        /// Sets the iterator to the given arc of the given digraph.
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        ///
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        ArcIt(const Digraph&, const Arc&) { }
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        /// Next arc
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        /// Assign the iterator to the next arc.
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        ///
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        ArcIt& operator++() { return *this; }
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      };
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      /// \brief The source node of the arc.
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      ///
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      /// Returns the source node of the given arc.
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      Node source(Arc) const { return INVALID; }
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      /// \brief The target node of the arc.
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      ///
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      /// Returns the target node of the given arc.
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      Node target(Arc) const { return INVALID; }
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      /// \brief The ID of the node.
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      ///
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      /// Returns the ID of the given node.
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      int id(Node) const { return -1; }
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      /// \brief The ID of the arc.
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      ///
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      /// Returns the ID of the given arc.
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      int id(Arc) const { return -1; }
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      /// \brief The node with the given ID.
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      ///
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      /// Returns the node with the given ID.
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      /// \pre The argument should be a valid node ID in the digraph.
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      Node nodeFromId(int) const { return INVALID; }
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      /// \brief The arc with the given ID.
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      ///
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      /// Returns the arc with the given ID.
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      /// \pre The argument should be a valid arc ID in the digraph.
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      Arc arcFromId(int) const { return INVALID; }
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      /// \brief An upper bound on the node IDs.
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      ///
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      /// Returns an upper bound on the node IDs.
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      int maxNodeId() const { return -1; }
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      /// \brief An upper bound on the arc IDs.
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      ///
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      /// Returns an upper bound on the arc IDs.
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      int maxArcId() const { return -1; }
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      void first(Node&) const {}
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      void next(Node&) const {}
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      void first(Arc&) const {}
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      void next(Arc&) const {}
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      void firstIn(Arc&, const Node&) const {}
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      void nextIn(Arc&) const {}
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      void firstOut(Arc&, const Node&) const {}
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      void nextOut(Arc&) const {}
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      // The second parameter is dummy.
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      Node fromId(int, Node) const { return INVALID; }
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      // The second parameter is dummy.
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      Arc fromId(int, Arc) const { return INVALID; }
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      // Dummy parameter.
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      int maxId(Node) const { return -1; }
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      // Dummy parameter.
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      int maxId(Arc) const { return -1; }
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      /// \brief The opposite node on the arc.
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      ///
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      /// Returns the opposite node on the given arc.
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      Node oppositeNode(Node, Arc) const { return INVALID; }
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      /// \brief The base node of the iterator.
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      ///
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      /// Returns the base node of the given outgoing arc iterator
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      /// (i.e. the source node of the corresponding arc).
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      Node baseNode(OutArcIt) const { return INVALID; }
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      /// \brief The running node of the iterator.
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      ///
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      /// Returns the running node of the given outgoing arc iterator
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      /// (i.e. the target node of the corresponding arc).
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      Node runningNode(OutArcIt) const { return INVALID; }
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      /// \brief The base node of the iterator.
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      ///
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      /// Returns the base node of the given incomming arc iterator
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      /// (i.e. the target node of the corresponding arc).
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      Node baseNode(InArcIt) const { return INVALID; }
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      /// \brief The running node of the iterator.
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      ///
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      /// Returns the running node of the given incomming arc iterator
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      /// (i.e. the source node of the corresponding arc).
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      Node runningNode(InArcIt) const { return INVALID; }
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      /// \brief Standard graph map type for the nodes.
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      ///
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      /// Standard graph map type for the nodes.
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      /// It conforms to the ReferenceMap concept.
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      template<class T>
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      class NodeMap : public ReferenceMap<Node, T, T&, const T&> {
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      public:
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        /// Constructor
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        explicit NodeMap(const Digraph&) { }
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        /// Constructor with given initial value
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        NodeMap(const Digraph&, T) { }
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      private:
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        ///Copy constructor
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        NodeMap(const NodeMap& nm) :
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          ReferenceMap<Node, T, T&, const T&>(nm) { }
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        ///Assignment operator
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        template <typename CMap>
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        NodeMap& operator=(const CMap&) {
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          checkConcept<ReadMap<Node, T>, CMap>();
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          return *this;
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        }
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      };
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      /// \brief Standard graph map type for the arcs.
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      ///
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      /// Standard graph map type for the arcs.
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      /// It conforms to the ReferenceMap concept.
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      template<class T>
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      class ArcMap : public ReferenceMap<Arc, T, T&, const T&> {
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      public:
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        /// Constructor
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        explicit ArcMap(const Digraph&) { }
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        /// Constructor with given initial value
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        ArcMap(const Digraph&, T) { }
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      private:
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        ///Copy constructor
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        ArcMap(const ArcMap& em) :
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          ReferenceMap<Arc, T, T&, const T&>(em) { }
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        ///Assignment operator
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        template <typename CMap>
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        ArcMap& operator=(const CMap&) {
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          checkConcept<ReadMap<Arc, T>, CMap>();
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          return *this;
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   469
        }
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      };
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      template <typename _Digraph>
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      struct Constraints {
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        void constraints() {
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          checkConcept<BaseDigraphComponent, _Digraph>();
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          checkConcept<IterableDigraphComponent<>, _Digraph>();
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          checkConcept<IDableDigraphComponent<>, _Digraph>();
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          checkConcept<MappableDigraphComponent<>, _Digraph>();
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   479
        }
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      };
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    };
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  } //namespace concepts
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} //namespace lemon
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#endif