kpeter@773: /* -*- C++ -*- kpeter@773: * kpeter@773: * This file is a part of LEMON, a generic C++ optimization library kpeter@773: * kpeter@773: * Copyright (C) 2003-2008 kpeter@773: * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport kpeter@773: * (Egervary Research Group on Combinatorial Optimization, EGRES). kpeter@773: * kpeter@773: * Permission to use, modify and distribute this software is granted kpeter@773: * provided that this copyright notice appears in all copies. For kpeter@773: * precise terms see the accompanying LICENSE file. kpeter@773: * kpeter@773: * This software is provided "AS IS" with no warranty of any kind, kpeter@773: * express or implied, and with no claim as to its suitability for any kpeter@773: * purpose. kpeter@773: * kpeter@773: */ kpeter@773: kpeter@773: #ifndef LEMON_STATIC_GRAPH_H kpeter@773: #define LEMON_STATIC_GRAPH_H kpeter@773: kpeter@773: ///\ingroup graphs kpeter@773: ///\file kpeter@773: ///\brief StaticDigraph class. kpeter@773: kpeter@773: #include kpeter@773: #include kpeter@773: kpeter@773: namespace lemon { kpeter@773: kpeter@773: class StaticDigraphBase { kpeter@773: public: kpeter@773: kpeter@773: StaticDigraphBase() kpeter@774: : built(false), node_num(0), arc_num(0), kpeter@773: node_first_out(NULL), node_first_in(NULL), kpeter@773: arc_source(NULL), arc_target(NULL), kpeter@773: arc_next_in(NULL), arc_next_out(NULL) {} kpeter@773: kpeter@773: ~StaticDigraphBase() { kpeter@774: if (built) { kpeter@773: delete[] node_first_out; kpeter@773: delete[] node_first_in; kpeter@773: delete[] arc_source; kpeter@773: delete[] arc_target; kpeter@773: delete[] arc_next_out; kpeter@773: delete[] arc_next_in; kpeter@773: } kpeter@773: } kpeter@773: kpeter@773: class Node { kpeter@773: friend class StaticDigraphBase; kpeter@773: protected: kpeter@773: int id; kpeter@773: Node(int _id) : id(_id) {} kpeter@773: public: kpeter@773: Node() {} kpeter@773: Node (Invalid) : id(-1) {} kpeter@773: bool operator==(const Node& node) const { return id == node.id; } kpeter@773: bool operator!=(const Node& node) const { return id != node.id; } kpeter@773: bool operator<(const Node& node) const { return id < node.id; } kpeter@773: }; kpeter@773: kpeter@773: class Arc { kpeter@773: friend class StaticDigraphBase; kpeter@773: protected: kpeter@773: int id; kpeter@773: Arc(int _id) : id(_id) {} kpeter@773: public: kpeter@773: Arc() { } kpeter@773: Arc (Invalid) : id(-1) {} kpeter@773: bool operator==(const Arc& arc) const { return id == arc.id; } kpeter@773: bool operator!=(const Arc& arc) const { return id != arc.id; } kpeter@773: bool operator<(const Arc& arc) const { return id < arc.id; } kpeter@773: }; kpeter@773: kpeter@773: Node source(const Arc& e) const { return Node(arc_source[e.id]); } kpeter@773: Node target(const Arc& e) const { return Node(arc_target[e.id]); } kpeter@773: kpeter@773: void first(Node& n) const { n.id = node_num - 1; } kpeter@773: static void next(Node& n) { --n.id; } kpeter@773: kpeter@773: void first(Arc& e) const { e.id = arc_num - 1; } kpeter@773: static void next(Arc& e) { --e.id; } kpeter@773: kpeter@773: void firstOut(Arc& e, const Node& n) const { kpeter@773: e.id = node_first_out[n.id] != node_first_out[n.id + 1] ? kpeter@773: node_first_out[n.id] : -1; kpeter@773: } kpeter@773: void nextOut(Arc& e) const { e.id = arc_next_out[e.id]; } kpeter@773: kpeter@773: void firstIn(Arc& e, const Node& n) const { e.id = node_first_in[n.id]; } kpeter@773: void nextIn(Arc& e) const { e.id = arc_next_in[e.id]; } kpeter@773: kpeter@778: static int id(const Node& n) { return n.id; } kpeter@778: static Node nodeFromId(int id) { return Node(id); } kpeter@773: int maxNodeId() const { return node_num - 1; } kpeter@773: kpeter@778: static int id(const Arc& e) { return e.id; } kpeter@778: static Arc arcFromId(int id) { return Arc(id); } kpeter@773: int maxArcId() const { return arc_num - 1; } kpeter@773: kpeter@773: typedef True NodeNumTag; kpeter@773: typedef True ArcNumTag; kpeter@773: kpeter@773: int nodeNum() const { return node_num; } kpeter@773: int arcNum() const { return arc_num; } kpeter@773: kpeter@773: private: kpeter@773: kpeter@773: template kpeter@773: class ArcLess { kpeter@773: public: kpeter@773: typedef typename Digraph::Arc Arc; kpeter@773: kpeter@773: ArcLess(const Digraph &_graph, const NodeRefMap& _nodeRef) kpeter@773: : digraph(_graph), nodeRef(_nodeRef) {} kpeter@773: kpeter@773: bool operator()(const Arc& left, const Arc& right) const { kpeter@773: return nodeRef[digraph.target(left)] < nodeRef[digraph.target(right)]; kpeter@773: } kpeter@773: private: kpeter@773: const Digraph& digraph; kpeter@773: const NodeRefMap& nodeRef; kpeter@773: }; kpeter@773: kpeter@773: public: kpeter@773: kpeter@773: typedef True BuildTag; kpeter@773: kpeter@774: void clear() { kpeter@774: if (built) { kpeter@773: delete[] node_first_out; kpeter@773: delete[] node_first_in; kpeter@773: delete[] arc_source; kpeter@773: delete[] arc_target; kpeter@773: delete[] arc_next_out; kpeter@773: delete[] arc_next_in; kpeter@773: } kpeter@774: built = false; kpeter@774: node_num = 0; kpeter@774: arc_num = 0; kpeter@774: } kpeter@774: kpeter@774: template kpeter@774: void build(const Digraph& digraph, NodeRefMap& nodeRef, ArcRefMap& arcRef) { kpeter@773: typedef typename Digraph::Node GNode; kpeter@773: typedef typename Digraph::Arc GArc; kpeter@773: kpeter@774: built = true; kpeter@774: kpeter@773: node_num = countNodes(digraph); kpeter@773: arc_num = countArcs(digraph); kpeter@773: kpeter@773: node_first_out = new int[node_num + 1]; kpeter@773: node_first_in = new int[node_num]; kpeter@773: kpeter@773: arc_source = new int[arc_num]; kpeter@773: arc_target = new int[arc_num]; kpeter@773: arc_next_out = new int[arc_num]; kpeter@773: arc_next_in = new int[arc_num]; kpeter@773: kpeter@773: int node_index = 0; kpeter@773: for (typename Digraph::NodeIt n(digraph); n != INVALID; ++n) { kpeter@773: nodeRef[n] = Node(node_index); kpeter@773: node_first_in[node_index] = -1; kpeter@773: ++node_index; kpeter@773: } kpeter@773: kpeter@773: ArcLess arcLess(digraph, nodeRef); kpeter@773: kpeter@773: int arc_index = 0; kpeter@773: for (typename Digraph::NodeIt n(digraph); n != INVALID; ++n) { kpeter@773: int source = nodeRef[n].id; kpeter@773: std::vector arcs; kpeter@773: for (typename Digraph::OutArcIt e(digraph, n); e != INVALID; ++e) { kpeter@773: arcs.push_back(e); kpeter@773: } kpeter@773: if (!arcs.empty()) { kpeter@773: node_first_out[source] = arc_index; kpeter@773: std::sort(arcs.begin(), arcs.end(), arcLess); kpeter@773: for (typename std::vector::iterator it = arcs.begin(); kpeter@773: it != arcs.end(); ++it) { kpeter@773: int target = nodeRef[digraph.target(*it)].id; kpeter@773: arcRef[*it] = Arc(arc_index); kpeter@773: arc_source[arc_index] = source; kpeter@773: arc_target[arc_index] = target; kpeter@773: arc_next_in[arc_index] = node_first_in[target]; kpeter@773: node_first_in[target] = arc_index; kpeter@773: arc_next_out[arc_index] = arc_index + 1; kpeter@773: ++arc_index; kpeter@773: } kpeter@773: arc_next_out[arc_index - 1] = -1; kpeter@773: } else { kpeter@773: node_first_out[source] = arc_index; kpeter@773: } kpeter@773: } kpeter@773: node_first_out[node_num] = arc_num; kpeter@773: } kpeter@777: kpeter@777: template kpeter@777: void build(int n, ArcListIterator first, ArcListIterator last) { kpeter@777: built = true; kpeter@777: kpeter@777: node_num = n; kpeter@777: arc_num = std::distance(first, last); kpeter@777: kpeter@777: node_first_out = new int[node_num + 1]; kpeter@777: node_first_in = new int[node_num]; kpeter@777: kpeter@777: arc_source = new int[arc_num]; kpeter@777: arc_target = new int[arc_num]; kpeter@777: arc_next_out = new int[arc_num]; kpeter@777: arc_next_in = new int[arc_num]; kpeter@777: kpeter@777: for (int i = 0; i != node_num; ++i) { kpeter@777: node_first_in[i] = -1; kpeter@777: } kpeter@777: kpeter@777: int arc_index = 0; kpeter@777: for (int i = 0; i != node_num; ++i) { kpeter@777: node_first_out[i] = arc_index; kpeter@777: for ( ; first != last && (*first).first == i; ++first) { kpeter@777: int j = (*first).second; kpeter@777: LEMON_ASSERT(j >= 0 && j < node_num, kpeter@777: "Wrong arc list for StaticDigraph::build()"); kpeter@777: arc_source[arc_index] = i; kpeter@777: arc_target[arc_index] = j; kpeter@777: arc_next_in[arc_index] = node_first_in[j]; kpeter@777: node_first_in[j] = arc_index; kpeter@777: arc_next_out[arc_index] = arc_index + 1; kpeter@777: ++arc_index; kpeter@777: } kpeter@777: if (arc_index > node_first_out[i]) kpeter@777: arc_next_out[arc_index - 1] = -1; kpeter@777: } kpeter@777: LEMON_ASSERT(first == last, kpeter@777: "Wrong arc list for StaticDigraph::build()"); kpeter@777: node_first_out[node_num] = arc_num; kpeter@777: } kpeter@773: kpeter@773: protected: kpeter@773: kpeter@773: void fastFirstOut(Arc& e, const Node& n) const { kpeter@773: e.id = node_first_out[n.id]; kpeter@773: } kpeter@773: kpeter@773: static void fastNextOut(Arc& e) { kpeter@773: ++e.id; kpeter@773: } kpeter@773: void fastLastOut(Arc& e, const Node& n) const { kpeter@773: e.id = node_first_out[n.id + 1]; kpeter@773: } kpeter@773: kpeter@774: protected: kpeter@774: bool built; kpeter@773: int node_num; kpeter@773: int arc_num; kpeter@773: int *node_first_out; kpeter@773: int *node_first_in; kpeter@773: int *arc_source; kpeter@773: int *arc_target; kpeter@773: int *arc_next_in; kpeter@773: int *arc_next_out; kpeter@773: }; kpeter@773: kpeter@773: typedef DigraphExtender ExtendedStaticDigraphBase; kpeter@773: kpeter@773: kpeter@775: /// \ingroup graphs kpeter@775: /// kpeter@775: /// \brief A static directed graph class. kpeter@775: /// kpeter@775: /// \ref StaticDigraph is a highly efficient digraph implementation, kpeter@775: /// but it is fully static. kpeter@775: /// It stores only two \c int values for each node and only four \c int kpeter@775: /// values for each arc. Moreover it provides faster item iteration than kpeter@775: /// \ref ListDigraph and \ref SmartDigraph, especially using \c OutArcIt kpeter@775: /// iterators, since its arcs are stored in an appropriate order. kpeter@775: /// However it only provides build() and clear() functions and does not kpeter@775: /// support any other modification of the digraph. kpeter@775: /// kpeter@776: /// Since this digraph structure is completely static, its nodes and arcs kpeter@776: /// can be indexed with integers from the ranges [0..nodeNum()-1] kpeter@776: /// and [0..arcNum()-1], respectively. kpeter@776: /// The index of an item is the same as its ID, it can be obtained kpeter@776: /// using the corresponding \ref index() or \ref concepts::Digraph::id() kpeter@776: /// "id()" function. A node or arc with a certain index can be obtained kpeter@776: /// using node() or arc(). kpeter@776: /// kpeter@775: /// This type fully conforms to the \ref concepts::Digraph "Digraph concept". kpeter@775: /// Most of its member functions and nested classes are documented kpeter@775: /// only in the concept class. kpeter@775: /// kpeter@787: /// This class provides constant time counting for nodes and arcs. kpeter@787: /// kpeter@775: /// \sa concepts::Digraph kpeter@773: class StaticDigraph : public ExtendedStaticDigraphBase { kpeter@773: public: kpeter@773: kpeter@773: typedef ExtendedStaticDigraphBase Parent; kpeter@774: kpeter@774: public: kpeter@774: kpeter@776: /// \brief Constructor kpeter@775: /// kpeter@776: /// Default constructor. kpeter@776: StaticDigraph() : Parent() {} kpeter@776: kpeter@776: /// \brief The node with the given index. kpeter@776: /// kpeter@776: /// This function returns the node with the given index. kpeter@776: /// \sa index() kpeter@778: static Node node(int ix) { return Parent::nodeFromId(ix); } kpeter@776: kpeter@776: /// \brief The arc with the given index. kpeter@776: /// kpeter@776: /// This function returns the arc with the given index. kpeter@776: /// \sa index() kpeter@778: static Arc arc(int ix) { return Parent::arcFromId(ix); } kpeter@776: kpeter@776: /// \brief The index of the given node. kpeter@776: /// kpeter@776: /// This function returns the index of the the given node. kpeter@776: /// \sa node() kpeter@778: static int index(Node node) { return Parent::id(node); } kpeter@776: kpeter@776: /// \brief The index of the given arc. kpeter@776: /// kpeter@776: /// This function returns the index of the the given arc. kpeter@776: /// \sa arc() kpeter@778: static int index(Arc arc) { return Parent::id(arc); } kpeter@776: kpeter@776: /// \brief Number of nodes. kpeter@776: /// kpeter@776: /// This function returns the number of nodes. kpeter@776: int nodeNum() const { return node_num; } kpeter@776: kpeter@776: /// \brief Number of arcs. kpeter@776: /// kpeter@776: /// This function returns the number of arcs. kpeter@776: int arcNum() const { return arc_num; } kpeter@776: kpeter@775: /// \brief Build the digraph copying another digraph. kpeter@775: /// kpeter@775: /// This function builds the digraph copying another digraph of any kpeter@775: /// kind. It can be called more than once, but in such case, the whole kpeter@775: /// structure and all maps will be cleared and rebuilt. kpeter@775: /// kpeter@775: /// This method also makes possible to copy a digraph to a StaticDigraph kpeter@775: /// structure using \ref DigraphCopy. kpeter@775: /// kpeter@775: /// \param digraph An existing digraph to be copied. kpeter@775: /// \param nodeRef The node references will be copied into this map. kpeter@775: /// Its key type must be \c Digraph::Node and its value type must be kpeter@775: /// \c StaticDigraph::Node. kpeter@775: /// It must conform to the \ref concepts::ReadWriteMap "ReadWriteMap" kpeter@775: /// concept. kpeter@775: /// \param arcRef The arc references will be copied into this map. kpeter@775: /// Its key type must be \c Digraph::Arc and its value type must be kpeter@775: /// \c StaticDigraph::Arc. kpeter@775: /// It must conform to the \ref concepts::WriteMap "WriteMap" concept. kpeter@775: /// kpeter@775: /// \note If you do not need the arc references, then you could use kpeter@775: /// \ref NullMap for the last parameter. However the node references kpeter@775: /// are required by the function itself, thus they must be readable kpeter@775: /// from the map. kpeter@774: template kpeter@774: void build(const Digraph& digraph, NodeRefMap& nodeRef, ArcRefMap& arcRef) { kpeter@774: if (built) Parent::clear(); kpeter@774: Parent::build(digraph, nodeRef, arcRef); kpeter@774: } kpeter@774: kpeter@777: /// \brief Build the digraph from an arc list. kpeter@777: /// kpeter@777: /// This function builds the digraph from the given arc list. kpeter@777: /// It can be called more than once, but in such case, the whole kpeter@777: /// structure and all maps will be cleared and rebuilt. kpeter@777: /// kpeter@777: /// The list of the arcs must be given in the range [begin, end) kpeter@777: /// specified by STL compatible itartors whose \c value_type must be kpeter@777: /// std::pair. kpeter@777: /// Each arc must be specified by a pair of integer indices kpeter@777: /// from the range [0..n-1]. The pairs must be in a kpeter@777: /// non-decreasing order with respect to their first values. kpeter@777: /// If the k-th pair in the list is (i,j), then kpeter@777: /// arc(k-1) will connect node(i) to node(j). kpeter@777: /// kpeter@777: /// \param n The number of nodes. kpeter@777: /// \param begin An iterator pointing to the beginning of the arc list. kpeter@777: /// \param end An iterator pointing to the end of the arc list. kpeter@777: /// kpeter@777: /// For example, a simple digraph can be constructed like this. kpeter@777: /// \code kpeter@777: /// std::vector > arcs; kpeter@777: /// arcs.push_back(std::make_pair(0,1)); kpeter@777: /// arcs.push_back(std::make_pair(0,2)); kpeter@777: /// arcs.push_back(std::make_pair(1,3)); kpeter@777: /// arcs.push_back(std::make_pair(1,2)); kpeter@777: /// arcs.push_back(std::make_pair(3,0)); kpeter@777: /// StaticDigraph gr; kpeter@777: /// gr.build(4, arcs.begin(), arcs.end()); kpeter@777: /// \endcode kpeter@777: template kpeter@777: void build(int n, ArcListIterator begin, ArcListIterator end) { kpeter@777: if (built) Parent::clear(); kpeter@777: StaticDigraphBase::build(n, begin, end); kpeter@777: notifier(Node()).build(); kpeter@777: notifier(Arc()).build(); kpeter@777: } kpeter@777: kpeter@776: /// \brief Clear the digraph. kpeter@776: /// kpeter@776: /// This function erases all nodes and arcs from the digraph. kpeter@776: void clear() { kpeter@776: Parent::clear(); kpeter@776: } kpeter@773: kpeter@773: protected: kpeter@773: kpeter@773: using Parent::fastFirstOut; kpeter@773: using Parent::fastNextOut; kpeter@773: using Parent::fastLastOut; kpeter@773: kpeter@773: public: kpeter@773: kpeter@773: class OutArcIt : public Arc { kpeter@773: public: kpeter@773: kpeter@773: OutArcIt() { } kpeter@773: kpeter@773: OutArcIt(Invalid i) : Arc(i) { } kpeter@773: kpeter@773: OutArcIt(const StaticDigraph& digraph, const Node& node) { kpeter@773: digraph.fastFirstOut(*this, node); kpeter@773: digraph.fastLastOut(last, node); kpeter@773: if (last == *this) *this = INVALID; kpeter@773: } kpeter@773: kpeter@773: OutArcIt(const StaticDigraph& digraph, const Arc& arc) : Arc(arc) { kpeter@773: if (arc != INVALID) { kpeter@773: digraph.fastLastOut(last, digraph.source(arc)); kpeter@773: } kpeter@773: } kpeter@773: kpeter@773: OutArcIt& operator++() { kpeter@773: StaticDigraph::fastNextOut(*this); kpeter@773: if (last == *this) *this = INVALID; kpeter@773: return *this; kpeter@773: } kpeter@773: kpeter@773: private: kpeter@773: Arc last; kpeter@773: }; kpeter@773: kpeter@774: Node baseNode(const OutArcIt &arc) const { kpeter@774: return Parent::source(static_cast(arc)); kpeter@774: } kpeter@774: kpeter@774: Node runningNode(const OutArcIt &arc) const { kpeter@774: return Parent::target(static_cast(arc)); kpeter@774: } kpeter@774: kpeter@774: Node baseNode(const InArcIt &arc) const { kpeter@774: return Parent::target(static_cast(arc)); kpeter@774: } kpeter@774: kpeter@774: Node runningNode(const InArcIt &arc) const { kpeter@774: return Parent::source(static_cast(arc)); kpeter@774: } kpeter@774: kpeter@773: }; kpeter@773: kpeter@773: } kpeter@773: kpeter@773: #endif