[797] | 1 | // -*- c++ -*- // |
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| 2 | |
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| 3 | /** |
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| 4 | @defgroup paths Path Structures |
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| 5 | @ingroup datas |
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| 6 | \brief Path structures implemented in Hugo. |
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| 7 | |
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| 8 | Hugolib provides flexible data structures |
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| 9 | to work with paths. |
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| 10 | |
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| 11 | All of them have the same interface, especially they can be built or extended |
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| 12 | using a standard Builder subclass. This make is easy to have e.g. the Dijkstra |
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| 13 | algorithm to store its result in any kind of path structure. |
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| 14 | |
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| 15 | */ |
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| 16 | |
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| 17 | ///\ingroup paths |
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| 18 | ///\file |
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| 19 | ///\brief Classes for representing paths in graphs. |
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| 20 | |
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| 21 | #ifndef HUGO_PATH_H |
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| 22 | #define HUGO_PATH_H |
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| 23 | |
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| 24 | #include <deque> |
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| 25 | #include <vector> |
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| 26 | #include <algorithm> |
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| 27 | |
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| 28 | #include <hugo/invalid.h> |
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| 29 | #include <hugo/error.h> |
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| 30 | #include <debug.h> |
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| 31 | |
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| 32 | namespace hugo { |
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| 33 | |
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| 34 | /// \addtogroup paths |
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| 35 | /// @{ |
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| 36 | |
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| 37 | |
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| 38 | //! \brief A structure for representing directed path in a graph. |
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| 39 | //! |
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| 40 | //! A structure for representing directed path in a graph. |
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| 41 | //! \param Graph The graph type in which the path is. |
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| 42 | //! \param DM DebugMode, defaults to DefaultDebugMode. |
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| 43 | //! |
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| 44 | //! In a sense, the path can be treated as a graph, for is has \c NodeIt |
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| 45 | //! and \c EdgeIt with the same usage. These types converts to the \c Node |
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| 46 | //! and \c Edge of the original graph. |
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| 47 | //! |
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| 48 | //! \todo Thoroughfully check all the range and consistency tests. |
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| 49 | template<typename Graph, typename DM = DefaultDebugMode> |
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| 50 | class DirPath { |
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| 51 | public: |
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| 52 | /// Edge type of the underlying graph. |
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| 53 | typedef typename Graph::Edge GraphEdge; |
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| 54 | /// Node type of the underlying graph. |
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| 55 | typedef typename Graph::Node GraphNode; |
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| 56 | class NodeIt; |
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| 57 | class EdgeIt; |
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| 58 | |
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| 59 | protected: |
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| 60 | const Graph *gr; |
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| 61 | typedef std::vector<GraphEdge> Container; |
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| 62 | Container edges; |
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| 63 | |
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| 64 | public: |
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| 65 | |
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| 66 | /// \param _G The graph in which the path is. |
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| 67 | /// |
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| 68 | DirPath(const Graph &_G) : gr(&_G) {} |
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| 69 | |
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| 70 | /// \brief Subpath constructor. |
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| 71 | /// |
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| 72 | /// Subpath defined by two nodes. |
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| 73 | /// \warning It is an error if the two edges are not in order! |
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| 74 | DirPath(const DirPath &P, const NodeIt &a, const NodeIt &b) { |
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| 75 | if( DM::range_check && (!a.valid() || !b.valid) ) { |
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| 76 | // FIXME: this check should be more elaborate... |
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| 77 | fault("DirPath, subpath ctor: invalid bounding nodes"); |
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| 78 | } |
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| 79 | gr = P.gr; |
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| 80 | edges.insert(edges.end(), P.edges.begin()+a.idx, P.edges.begin()+b.idx); |
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| 81 | } |
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| 82 | |
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| 83 | /// \brief Subpath constructor. |
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| 84 | /// |
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| 85 | /// Subpath defined by two edges. Contains edges in [a,b) |
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| 86 | /// \warning It is an error if the two edges are not in order! |
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| 87 | DirPath(const DirPath &P, const EdgeIt &a, const EdgeIt &b) { |
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| 88 | if( DM::range_check && (!a.valid() || !b.valid) ) { |
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| 89 | // FIXME: this check should be more elaborate... |
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| 90 | fault("DirPath, subpath ctor: invalid bounding nodes"); |
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| 91 | } |
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| 92 | gr = P.gr; |
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| 93 | edges.insert(edges.end(), P.edges.begin()+a.idx, P.edges.begin()+b.idx); |
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| 94 | } |
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| 95 | |
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| 96 | /// Length of the path. |
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| 97 | size_t length() const { return edges.size(); } |
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| 98 | /// Returns whether the path is empty. |
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| 99 | bool empty() const { return edges.empty(); } |
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| 100 | |
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| 101 | /// Resets the path to an empty path. |
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| 102 | void clear() { edges.clear(); } |
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| 103 | |
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| 104 | /// \brief Starting point of the path. |
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| 105 | /// |
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| 106 | /// Starting point of the path. |
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| 107 | /// Returns INVALID if the path is empty. |
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| 108 | GraphNode from() const { |
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| 109 | return empty() ? INVALID : gr->tail(edges[0]); |
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| 110 | } |
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| 111 | /// \brief End point of the path. |
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| 112 | /// |
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| 113 | /// End point of the path. |
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| 114 | /// Returns INVALID if the path is empty. |
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| 115 | GraphNode to() const { |
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| 116 | return empty() ? INVALID : gr->head(edges[length()-1]); |
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| 117 | } |
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| 118 | |
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| 119 | /// \brief Initializes node or edge iterator to point to the first |
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| 120 | /// node or edge. |
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| 121 | /// |
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| 122 | /// \sa nth |
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| 123 | template<typename It> |
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| 124 | It& first(It &i) const { return i=It(*this); } |
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| 125 | |
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| 126 | /// \brief Initializes node iterator to point to the node of a given index. |
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| 127 | NodeIt& nth(NodeIt &i, int n) const { |
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| 128 | if( DM::range_check && (n<0 || n>int(length())) ) |
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| 129 | fault("DirPath::nth: index out of range"); |
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| 130 | return i=NodeIt(*this, n); |
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| 131 | } |
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| 132 | |
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| 133 | /// \brief Initializes edge iterator to point to the edge of a given index. |
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| 134 | EdgeIt& nth(EdgeIt &i, int n) const { |
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| 135 | if( DM::range_check && (n<0 || n>=int(length())) ) |
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| 136 | fault("DirPath::nth: index out of range"); |
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| 137 | return i=EdgeIt(*this, n); |
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| 138 | } |
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| 139 | |
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| 140 | /// Checks validity of a node or edge iterator. |
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| 141 | template<typename It> |
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| 142 | static |
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| 143 | bool valid(const It &i) { return i.valid(); } |
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| 144 | |
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| 145 | /// Steps the given node or edge iterator. |
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| 146 | template<typename It> |
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| 147 | static |
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| 148 | It& next(It &e) { |
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| 149 | if( DM::range_check && !e.valid() ) |
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| 150 | fault("DirPath::next() on invalid iterator"); |
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| 151 | return ++e; |
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| 152 | } |
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| 153 | |
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| 154 | /// \brief Returns node iterator pointing to the head node of the |
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| 155 | /// given edge iterator. |
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| 156 | NodeIt head(const EdgeIt& e) const { |
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| 157 | if( DM::range_check && !e.valid() ) |
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| 158 | fault("DirPath::head() on invalid iterator"); |
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| 159 | return NodeIt(*this, e.idx+1); |
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| 160 | } |
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| 161 | |
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| 162 | /// \brief Returns node iterator pointing to the tail node of the |
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| 163 | /// given edge iterator. |
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| 164 | NodeIt tail(const EdgeIt& e) const { |
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| 165 | if( DM::range_check && !e.valid() ) |
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| 166 | fault("DirPath::tail() on invalid iterator"); |
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| 167 | return NodeIt(*this, e.idx); |
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| 168 | } |
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| 169 | |
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| 170 | |
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| 171 | /* Iterator classes */ |
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| 172 | |
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| 173 | /** |
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| 174 | * \brief Iterator class to iterate on the edges of the paths |
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| 175 | * |
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| 176 | * \ingroup paths |
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| 177 | * This class is used to iterate on the edges of the paths |
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| 178 | * |
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| 179 | * Of course it converts to Graph::Edge |
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| 180 | * |
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| 181 | * \todo Its interface differs from the standard edge iterator. |
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| 182 | * Yes, it shouldn't. |
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| 183 | */ |
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| 184 | class EdgeIt { |
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| 185 | friend class DirPath; |
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| 186 | |
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| 187 | int idx; |
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| 188 | const DirPath *p; |
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| 189 | public: |
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| 190 | /// Default constructor |
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| 191 | EdgeIt() {} |
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| 192 | /// Invalid constructor |
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| 193 | EdgeIt(Invalid) : idx(-1), p(0) {} |
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| 194 | /// Constructor with starting point |
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| 195 | EdgeIt(const DirPath &_p, int _idx = 0) : |
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| 196 | idx(_idx), p(&_p) { validate(); } |
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| 197 | |
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| 198 | ///Validity check |
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| 199 | bool valid() const { return idx!=-1; } |
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| 200 | |
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| 201 | ///Conversion to Graph::Edge |
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| 202 | operator GraphEdge () const { |
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| 203 | return valid() ? p->edges[idx] : INVALID; |
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| 204 | } |
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| 205 | |
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| 206 | /// Next edge |
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| 207 | EdgeIt& operator++() { ++idx; validate(); return *this; } |
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| 208 | |
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| 209 | /// Comparison operator |
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| 210 | bool operator==(const EdgeIt& e) const { return idx==e.idx; } |
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| 211 | /// Comparison operator |
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| 212 | bool operator!=(const EdgeIt& e) const { return idx!=e.idx; } |
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| 213 | /// Comparison operator |
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| 214 | bool operator<(const EdgeIt& e) const { return idx<e.idx; } |
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| 215 | |
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| 216 | private: |
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| 217 | // FIXME: comparison between signed and unsigned... |
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| 218 | // Jo ez igy? Vagy esetleg legyen a length() int? |
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| 219 | void validate() { if( size_t(idx) >= p->length() ) idx=-1; } |
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| 220 | }; |
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| 221 | |
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| 222 | /** |
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| 223 | * \brief Iterator class to iterate on the nodes of the paths |
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| 224 | * |
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| 225 | * \ingroup paths |
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| 226 | * This class is used to iterate on the nodes of the paths |
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| 227 | * |
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| 228 | * Of course it converts to Graph::Node |
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| 229 | * |
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| 230 | * \todo Its interface differs from the standard node iterator. |
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| 231 | * Yes, it shouldn't. |
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| 232 | */ |
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| 233 | class NodeIt { |
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| 234 | friend class DirPath; |
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| 235 | |
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| 236 | int idx; |
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| 237 | const DirPath *p; |
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| 238 | public: |
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| 239 | /// Default constructor |
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| 240 | NodeIt() {} |
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| 241 | /// Invalid constructor |
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| 242 | NodeIt(Invalid) : idx(-1), p(0) {} |
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| 243 | /// Constructor with starting point |
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| 244 | NodeIt(const DirPath &_p, int _idx = 0) : |
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| 245 | idx(_idx), p(&_p) { validate(); } |
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| 246 | |
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| 247 | ///Validity check |
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| 248 | bool valid() const { return idx!=-1; } |
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| 249 | |
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| 250 | ///Conversion to Graph::Node |
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| 251 | operator const GraphNode& () const { |
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| 252 | if(idx >= p->length()) |
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| 253 | return p->to(); |
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| 254 | else if(idx >= 0) |
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| 255 | return p->gr->tail(p->edges[idx]); |
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| 256 | else |
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| 257 | return INVALID; |
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| 258 | } |
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| 259 | /// Next node |
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| 260 | NodeIt& operator++() { ++idx; validate(); return *this; } |
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| 261 | |
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| 262 | /// Comparison operator |
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| 263 | bool operator==(const NodeIt& e) const { return idx==e.idx; } |
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| 264 | /// Comparison operator |
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| 265 | bool operator!=(const NodeIt& e) const { return idx!=e.idx; } |
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| 266 | /// Comparison operator |
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| 267 | bool operator<(const NodeIt& e) const { return idx<e.idx; } |
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| 268 | |
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| 269 | private: |
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| 270 | void validate() { if( size_t(idx) > p->length() ) idx=-1; } |
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| 271 | }; |
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| 272 | |
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| 273 | friend class Builder; |
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| 274 | |
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| 275 | /** |
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| 276 | * \brief Class to build paths |
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| 277 | * |
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| 278 | * \ingroup paths |
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| 279 | * This class is used to fill a path with edges. |
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| 280 | * |
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| 281 | * You can push new edges to the front and to the back of the path in |
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| 282 | * arbitrary order then you should commit these changes to the graph. |
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| 283 | * |
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| 284 | * Fundamentally, for most "Paths" (classes fulfilling the |
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| 285 | * PathConcept) while the builder is active (after the first modifying |
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| 286 | * operation and until the commit()) the original Path is in a |
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| 287 | * "transitional" state (operations on it have undefined result). But |
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| 288 | * in the case of DirPath the original path remains unchanged until the |
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| 289 | * commit. However we don't recomend that you use this feature. |
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| 290 | */ |
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| 291 | class Builder { |
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| 292 | DirPath &P; |
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| 293 | Container front, back; |
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| 294 | |
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| 295 | public: |
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| 296 | ///\param _P the path you want to fill in. |
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| 297 | /// |
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| 298 | Builder(DirPath &_P) : P(_P) {} |
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| 299 | |
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| 300 | /// Sets the starting node of the path. |
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| 301 | |
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| 302 | /// Sets the starting node of the path. Edge added to the path |
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| 303 | /// afterwards have to be incident to this node. |
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| 304 | /// It should be called iff the path is empty and before any call to |
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| 305 | /// \ref pushFront() or \ref pushBack() |
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| 306 | void setStart(const GraphNode &) {} |
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| 307 | |
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| 308 | ///Push a new edge to the front of the path |
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| 309 | |
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| 310 | ///Push a new edge to the front of the path. |
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| 311 | ///\sa setStart |
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| 312 | void pushFront(const GraphEdge& e) { |
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| 313 | if( DM::consistensy_check && !empty() && P.gr->head(e)!=from() ) { |
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| 314 | fault("DirPath::Builder::pushFront: nonincident edge"); |
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| 315 | } |
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| 316 | front.push_back(e); |
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| 317 | } |
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| 318 | |
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| 319 | ///Push a new edge to the back of the path |
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| 320 | |
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| 321 | ///Push a new edge to the back of the path. |
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| 322 | ///\sa setStart |
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| 323 | void pushBack(const GraphEdge& e) { |
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| 324 | if( DM::consistensy_check && !empty() && P.gr->tail(e)!=to() ) { |
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| 325 | fault("DirPath::Builder::pushBack: nonincident edge"); |
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| 326 | } |
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| 327 | back.push_back(e); |
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| 328 | } |
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| 329 | |
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| 330 | ///Commit the changes to the path. |
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| 331 | void commit() { |
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| 332 | if( !(front.empty() && back.empty()) ) { |
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| 333 | Container tmp; |
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| 334 | tmp.reserve(front.size()+back.size()+P.length()); |
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| 335 | tmp.insert(tmp.end(), front.rbegin(), front.rend()); |
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| 336 | tmp.insert(tmp.end(), P.edges.begin(), P.edges.end()); |
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| 337 | tmp.insert(tmp.end(), back.begin(), back.end()); |
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| 338 | P.edges.swap(tmp); |
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| 339 | front.clear(); |
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| 340 | back.clear(); |
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| 341 | } |
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| 342 | } |
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| 343 | |
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| 344 | // FIXME: Hmm, pontosan hogy is kene ezt csinalni? |
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| 345 | // Hogy kenyelmes egy ilyet hasznalni? |
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| 346 | |
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| 347 | ///Reserve storage in advance for the builder |
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| 348 | |
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| 349 | ///If you know an reasonable upper bound of the number of the edges |
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| 350 | ///to add, using this function you can speed up the building. |
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| 351 | void reserve(size_t r) { |
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| 352 | front.reserve(r); |
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| 353 | back.reserve(r); |
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| 354 | } |
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| 355 | |
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| 356 | private: |
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| 357 | bool empty() { |
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| 358 | return front.empty() && back.empty() && P.empty(); |
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| 359 | } |
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| 360 | |
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| 361 | GraphNode from() const { |
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| 362 | if( ! front.empty() ) |
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| 363 | return P.gr->tail(front[front.size()-1]); |
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| 364 | else if( ! P.empty() ) |
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| 365 | return P.gr->tail(P.edges[0]); |
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| 366 | else if( ! back.empty() ) |
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| 367 | return P.gr->tail(back[0]); |
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| 368 | else |
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| 369 | return INVALID; |
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| 370 | } |
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| 371 | GraphNode to() const { |
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| 372 | if( ! back.empty() ) |
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| 373 | return P.gr->head(back[back.size()-1]); |
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| 374 | else if( ! P.empty() ) |
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| 375 | return P.gr->head(P.edges[P.length()-1]); |
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| 376 | else if( ! front.empty() ) |
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| 377 | return P.gr->head(front[0]); |
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| 378 | else |
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| 379 | return INVALID; |
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| 380 | } |
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| 381 | |
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| 382 | }; |
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| 383 | |
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| 384 | }; |
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| 385 | |
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| 386 | |
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| 387 | |
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| 388 | |
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| 389 | |
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| 390 | |
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| 391 | |
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| 392 | |
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| 393 | |
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| 394 | |
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| 395 | /**********************************************************************/ |
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| 396 | |
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| 397 | |
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| 398 | //! \brief A structure for representing undirected path in a graph. |
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| 399 | //! |
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| 400 | //! A structure for representing undirected path in a graph. Ie. this is |
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| 401 | //! a path in a \e directed graph but the edges should not be directed |
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| 402 | //! forward. |
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| 403 | //! |
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| 404 | //! \param Graph The graph type in which the path is. |
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| 405 | //! \param DM DebugMode, defaults to DefaultDebugMode. |
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| 406 | //! |
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| 407 | //! In a sense, the path can be treated as a graph, for is has \c NodeIt |
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| 408 | //! and \c EdgeIt with the same usage. These types converts to the \c Node |
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| 409 | //! and \c Edge of the original graph. |
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| 410 | //! |
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| 411 | //! \todo Thoroughfully check all the range and consistency tests. |
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| 412 | template<typename Graph, typename DM = DefaultDebugMode> |
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| 413 | class UndirPath { |
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| 414 | public: |
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| 415 | /// Edge type of the underlying graph. |
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| 416 | typedef typename Graph::Edge GraphEdge; |
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| 417 | /// Node type of the underlying graph. |
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| 418 | typedef typename Graph::Node GraphNode; |
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| 419 | class NodeIt; |
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| 420 | class EdgeIt; |
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| 421 | |
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| 422 | protected: |
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| 423 | const Graph *gr; |
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| 424 | typedef std::vector<GraphEdge> Container; |
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| 425 | Container edges; |
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| 426 | |
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| 427 | public: |
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| 428 | |
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| 429 | /// \param _G The graph in which the path is. |
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| 430 | /// |
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| 431 | UndirPath(const Graph &_G) : gr(&_G) {} |
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| 432 | |
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| 433 | /// \brief Subpath constructor. |
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| 434 | /// |
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| 435 | /// Subpath defined by two nodes. |
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| 436 | /// \warning It is an error if the two edges are not in order! |
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| 437 | UndirPath(const UndirPath &P, const NodeIt &a, const NodeIt &b) { |
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| 438 | if( DM::range_check && (!a.valid() || !b.valid) ) { |
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| 439 | // FIXME: this check should be more elaborate... |
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| 440 | fault("UndirPath, subpath ctor: invalid bounding nodes"); |
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| 441 | } |
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| 442 | gr = P.gr; |
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| 443 | edges.insert(edges.end(), P.edges.begin()+a.idx, P.edges.begin()+b.idx); |
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| 444 | } |
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| 445 | |
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| 446 | /// \brief Subpath constructor. |
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| 447 | /// |
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| 448 | /// Subpath defined by two edges. Contains edges in [a,b) |
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| 449 | /// \warning It is an error if the two edges are not in order! |
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| 450 | UndirPath(const UndirPath &P, const EdgeIt &a, const EdgeIt &b) { |
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| 451 | if( DM::range_check && (!a.valid() || !b.valid) ) { |
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| 452 | // FIXME: this check should be more elaborate... |
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| 453 | fault("UndirPath, subpath ctor: invalid bounding nodes"); |
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| 454 | } |
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| 455 | gr = P.gr; |
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| 456 | edges.insert(edges.end(), P.edges.begin()+a.idx, P.edges.begin()+b.idx); |
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| 457 | } |
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| 458 | |
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| 459 | /// Length of the path. |
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| 460 | size_t length() const { return edges.size(); } |
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| 461 | /// Returns whether the path is empty. |
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| 462 | bool empty() const { return edges.empty(); } |
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| 463 | |
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| 464 | /// Resets the path to an empty path. |
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| 465 | void clear() { edges.clear(); } |
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| 466 | |
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| 467 | /// \brief Starting point of the path. |
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| 468 | /// |
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| 469 | /// Starting point of the path. |
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| 470 | /// Returns INVALID if the path is empty. |
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| 471 | GraphNode from() const { |
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| 472 | return empty() ? INVALID : gr->tail(edges[0]); |
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| 473 | } |
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| 474 | /// \brief End point of the path. |
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| 475 | /// |
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| 476 | /// End point of the path. |
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| 477 | /// Returns INVALID if the path is empty. |
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| 478 | GraphNode to() const { |
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| 479 | return empty() ? INVALID : gr->head(edges[length()-1]); |
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| 480 | } |
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| 481 | |
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| 482 | /// \brief Initializes node or edge iterator to point to the first |
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| 483 | /// node or edge. |
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| 484 | /// |
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| 485 | /// \sa nth |
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| 486 | template<typename It> |
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| 487 | It& first(It &i) const { return i=It(*this); } |
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| 488 | |
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| 489 | /// \brief Initializes node iterator to point to the node of a given index. |
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| 490 | NodeIt& nth(NodeIt &i, int n) const { |
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| 491 | if( DM::range_check && (n<0 || n>int(length())) ) |
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| 492 | fault("UndirPath::nth: index out of range"); |
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| 493 | return i=NodeIt(*this, n); |
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| 494 | } |
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| 495 | |
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| 496 | /// \brief Initializes edge iterator to point to the edge of a given index. |
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| 497 | EdgeIt& nth(EdgeIt &i, int n) const { |
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| 498 | if( DM::range_check && (n<0 || n>=int(length())) ) |
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| 499 | fault("UndirPath::nth: index out of range"); |
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| 500 | return i=EdgeIt(*this, n); |
---|
| 501 | } |
---|
| 502 | |
---|
| 503 | /// Checks validity of a node or edge iterator. |
---|
| 504 | template<typename It> |
---|
| 505 | static |
---|
| 506 | bool valid(const It &i) { return i.valid(); } |
---|
| 507 | |
---|
| 508 | /// Steps the given node or edge iterator. |
---|
| 509 | template<typename It> |
---|
| 510 | static |
---|
| 511 | It& next(It &e) { |
---|
| 512 | if( DM::range_check && !e.valid() ) |
---|
| 513 | fault("UndirPath::next() on invalid iterator"); |
---|
| 514 | return ++e; |
---|
| 515 | } |
---|
| 516 | |
---|
| 517 | /// \brief Returns node iterator pointing to the head node of the |
---|
| 518 | /// given edge iterator. |
---|
| 519 | NodeIt head(const EdgeIt& e) const { |
---|
| 520 | if( DM::range_check && !e.valid() ) |
---|
| 521 | fault("UndirPath::head() on invalid iterator"); |
---|
| 522 | return NodeIt(*this, e.idx+1); |
---|
| 523 | } |
---|
| 524 | |
---|
| 525 | /// \brief Returns node iterator pointing to the tail node of the |
---|
| 526 | /// given edge iterator. |
---|
| 527 | NodeIt tail(const EdgeIt& e) const { |
---|
| 528 | if( DM::range_check && !e.valid() ) |
---|
| 529 | fault("UndirPath::tail() on invalid iterator"); |
---|
| 530 | return NodeIt(*this, e.idx); |
---|
| 531 | } |
---|
| 532 | |
---|
| 533 | |
---|
| 534 | |
---|
| 535 | /** |
---|
| 536 | * \brief Iterator class to iterate on the edges of the paths |
---|
| 537 | * |
---|
| 538 | * \ingroup paths |
---|
| 539 | * This class is used to iterate on the edges of the paths |
---|
| 540 | * |
---|
| 541 | * Of course it converts to Graph::Edge |
---|
| 542 | * |
---|
| 543 | * \todo Its interface differs from the standard edge iterator. |
---|
| 544 | * Yes, it shouldn't. |
---|
| 545 | */ |
---|
| 546 | class EdgeIt { |
---|
| 547 | friend class UndirPath; |
---|
| 548 | |
---|
| 549 | int idx; |
---|
| 550 | const UndirPath *p; |
---|
| 551 | public: |
---|
| 552 | /// Default constructor |
---|
| 553 | EdgeIt() {} |
---|
| 554 | /// Invalid constructor |
---|
| 555 | EdgeIt(Invalid) : idx(-1), p(0) {} |
---|
| 556 | /// Constructor with starting point |
---|
| 557 | EdgeIt(const UndirPath &_p, int _idx = 0) : |
---|
| 558 | idx(_idx), p(&_p) { validate(); } |
---|
| 559 | |
---|
| 560 | ///Validity check |
---|
| 561 | bool valid() const { return idx!=-1; } |
---|
| 562 | |
---|
| 563 | ///Conversion to Graph::Edge |
---|
| 564 | operator GraphEdge () const { |
---|
| 565 | return valid() ? p->edges[idx] : INVALID; |
---|
| 566 | } |
---|
| 567 | /// Next edge |
---|
| 568 | EdgeIt& operator++() { ++idx; validate(); return *this; } |
---|
| 569 | |
---|
| 570 | /// Comparison operator |
---|
| 571 | bool operator==(const EdgeIt& e) const { return idx==e.idx; } |
---|
| 572 | /// Comparison operator |
---|
| 573 | bool operator!=(const EdgeIt& e) const { return idx!=e.idx; } |
---|
| 574 | /// Comparison operator |
---|
| 575 | bool operator<(const EdgeIt& e) const { return idx<e.idx; } |
---|
| 576 | |
---|
| 577 | private: |
---|
| 578 | // FIXME: comparison between signed and unsigned... |
---|
| 579 | // Jo ez igy? Vagy esetleg legyen a length() int? |
---|
| 580 | void validate() { if( size_t(idx) >= p->length() ) idx=-1; } |
---|
| 581 | }; |
---|
| 582 | |
---|
| 583 | /** |
---|
| 584 | * \brief Iterator class to iterate on the nodes of the paths |
---|
| 585 | * |
---|
| 586 | * \ingroup paths |
---|
| 587 | * This class is used to iterate on the nodes of the paths |
---|
| 588 | * |
---|
| 589 | * Of course it converts to Graph::Node |
---|
| 590 | * |
---|
| 591 | * \todo Its interface differs from the standard node iterator. |
---|
| 592 | * Yes, it shouldn't. |
---|
| 593 | */ |
---|
| 594 | class NodeIt { |
---|
| 595 | friend class UndirPath; |
---|
| 596 | |
---|
| 597 | int idx; |
---|
| 598 | const UndirPath *p; |
---|
| 599 | public: |
---|
| 600 | /// Default constructor |
---|
| 601 | NodeIt() {} |
---|
| 602 | /// Invalid constructor |
---|
| 603 | NodeIt(Invalid) : idx(-1), p(0) {} |
---|
| 604 | /// Constructor with starting point |
---|
| 605 | NodeIt(const UndirPath &_p, int _idx = 0) : |
---|
| 606 | idx(_idx), p(&_p) { validate(); } |
---|
| 607 | |
---|
| 608 | ///Validity check |
---|
| 609 | bool valid() const { return idx!=-1; } |
---|
| 610 | |
---|
| 611 | ///Conversion to Graph::Node |
---|
| 612 | operator const GraphNode& () const { |
---|
| 613 | if(idx >= p->length()) |
---|
| 614 | return p->to(); |
---|
| 615 | else if(idx >= 0) |
---|
| 616 | return p->gr->tail(p->edges[idx]); |
---|
| 617 | else |
---|
| 618 | return INVALID; |
---|
| 619 | } |
---|
| 620 | /// Next node |
---|
| 621 | NodeIt& operator++() { ++idx; validate(); return *this; } |
---|
| 622 | |
---|
| 623 | /// Comparison operator |
---|
| 624 | bool operator==(const NodeIt& e) const { return idx==e.idx; } |
---|
| 625 | /// Comparison operator |
---|
| 626 | bool operator!=(const NodeIt& e) const { return idx!=e.idx; } |
---|
| 627 | /// Comparison operator |
---|
| 628 | bool operator<(const NodeIt& e) const { return idx<e.idx; } |
---|
| 629 | |
---|
| 630 | private: |
---|
| 631 | void validate() { if( size_t(idx) > p->length() ) idx=-1; } |
---|
| 632 | }; |
---|
| 633 | |
---|
| 634 | friend class Builder; |
---|
| 635 | |
---|
| 636 | /** |
---|
| 637 | * \brief Class to build paths |
---|
| 638 | * |
---|
| 639 | * \ingroup paths |
---|
| 640 | * This class is used to fill a path with edges. |
---|
| 641 | * |
---|
| 642 | * You can push new edges to the front and to the back of the path in |
---|
| 643 | * arbitrary order then you should commit these changes to the graph. |
---|
| 644 | * |
---|
| 645 | * Fundamentally, for most "Paths" (classes fulfilling the |
---|
| 646 | * PathConcept) while the builder is active (after the first modifying |
---|
| 647 | * operation and until the commit()) the original Path is in a |
---|
| 648 | * "transitional" state (operations ot it have undefined result). But |
---|
| 649 | * in the case of UndirPath the original path is unchanged until the |
---|
| 650 | * commit. However we don't recomend that you use this feature. |
---|
| 651 | */ |
---|
| 652 | class Builder { |
---|
| 653 | UndirPath &P; |
---|
| 654 | Container front, back; |
---|
| 655 | |
---|
| 656 | public: |
---|
| 657 | ///\param _P the path you want to fill in. |
---|
| 658 | /// |
---|
| 659 | Builder(UndirPath &_P) : P(_P) {} |
---|
| 660 | |
---|
| 661 | /// Sets the starting node of the path. |
---|
| 662 | |
---|
| 663 | /// Sets the starting node of the path. Edge added to the path |
---|
| 664 | /// afterwards have to be incident to this node. |
---|
| 665 | /// It should be called iff the path is empty and before any call to |
---|
| 666 | /// \ref pushFront() or \ref pushBack() |
---|
| 667 | void setStart(const GraphNode &) {} |
---|
| 668 | |
---|
| 669 | ///Push a new edge to the front of the path |
---|
| 670 | |
---|
| 671 | ///Push a new edge to the front of the path. |
---|
| 672 | ///\sa setStart |
---|
| 673 | void pushFront(const GraphEdge& e) { |
---|
| 674 | if( DM::consistensy_check && !empty() && P.gr->head(e)!=from() ) { |
---|
| 675 | fault("UndirPath::Builder::pushFront: nonincident edge"); |
---|
| 676 | } |
---|
| 677 | front.push_back(e); |
---|
| 678 | } |
---|
| 679 | |
---|
| 680 | ///Push a new edge to the back of the path |
---|
| 681 | |
---|
| 682 | ///Push a new edge to the back of the path. |
---|
| 683 | ///\sa setStart |
---|
| 684 | void pushBack(const GraphEdge& e) { |
---|
| 685 | if( DM::consistensy_check && !empty() && P.gr->tail(e)!=to() ) { |
---|
| 686 | fault("UndirPath::Builder::pushBack: nonincident edge"); |
---|
| 687 | } |
---|
| 688 | back.push_back(e); |
---|
| 689 | } |
---|
| 690 | |
---|
| 691 | ///Commit the changes to the path. |
---|
| 692 | void commit() { |
---|
| 693 | if( !(front.empty() && back.empty()) ) { |
---|
| 694 | Container tmp; |
---|
| 695 | tmp.reserve(front.size()+back.size()+P.length()); |
---|
| 696 | tmp.insert(tmp.end(), front.rbegin(), front.rend()); |
---|
| 697 | tmp.insert(tmp.end(), P.edges.begin(), P.edges.end()); |
---|
| 698 | tmp.insert(tmp.end(), back.begin(), back.end()); |
---|
| 699 | P.edges.swap(tmp); |
---|
| 700 | front.clear(); |
---|
| 701 | back.clear(); |
---|
| 702 | } |
---|
| 703 | } |
---|
| 704 | |
---|
| 705 | // FIXME: Hmm, pontosan hogy is kene ezt csinalni? |
---|
| 706 | // Hogy kenyelmes egy ilyet hasznalni? |
---|
| 707 | |
---|
| 708 | ///Reserve storage in advance for the builder |
---|
| 709 | |
---|
| 710 | ///If you know an reasonable upper bound of the number of the edges |
---|
| 711 | ///to add, using this function you can speed up the building. |
---|
| 712 | void reserve(size_t r) { |
---|
| 713 | front.reserve(r); |
---|
| 714 | back.reserve(r); |
---|
| 715 | } |
---|
| 716 | |
---|
| 717 | private: |
---|
| 718 | bool empty() { |
---|
| 719 | return front.empty() && back.empty() && P.empty(); |
---|
| 720 | } |
---|
| 721 | |
---|
| 722 | GraphNode from() const { |
---|
| 723 | if( ! front.empty() ) |
---|
| 724 | return P.gr->tail(front[front.size()-1]); |
---|
| 725 | else if( ! P.empty() ) |
---|
| 726 | return P.gr->tail(P.edges[0]); |
---|
| 727 | else if( ! back.empty() ) |
---|
| 728 | return P.gr->tail(back[0]); |
---|
| 729 | else |
---|
| 730 | return INVALID; |
---|
| 731 | } |
---|
| 732 | GraphNode to() const { |
---|
| 733 | if( ! back.empty() ) |
---|
| 734 | return P.gr->head(back[back.size()-1]); |
---|
| 735 | else if( ! P.empty() ) |
---|
| 736 | return P.gr->head(P.edges[P.length()-1]); |
---|
| 737 | else if( ! front.empty() ) |
---|
| 738 | return P.gr->head(front[0]); |
---|
| 739 | else |
---|
| 740 | return INVALID; |
---|
| 741 | } |
---|
| 742 | |
---|
| 743 | }; |
---|
| 744 | |
---|
| 745 | }; |
---|
| 746 | |
---|
| 747 | |
---|
| 748 | |
---|
| 749 | |
---|
| 750 | |
---|
| 751 | |
---|
| 752 | |
---|
| 753 | |
---|
| 754 | |
---|
| 755 | |
---|
| 756 | /**********************************************************************/ |
---|
| 757 | |
---|
| 758 | |
---|
| 759 | /* Ennek az allocatorosdinak sokkal jobban utana kene nezni a hasznalata |
---|
| 760 | elott. Eleg bonyinak nez ki, ahogyan azokat az STL-ben hasznaljak. */ |
---|
| 761 | |
---|
| 762 | template<typename Graph> |
---|
| 763 | class DynamicPath { |
---|
| 764 | |
---|
| 765 | public: |
---|
| 766 | typedef typename Graph::Edge GraphEdge; |
---|
| 767 | typedef typename Graph::Node GraphNode; |
---|
| 768 | class NodeIt; |
---|
| 769 | class EdgeIt; |
---|
| 770 | |
---|
| 771 | protected: |
---|
| 772 | Graph& G; |
---|
| 773 | // FIXME: ehelyett eleg lenne tarolni ket boolt: a ket szelso el |
---|
| 774 | // iranyitasat: |
---|
| 775 | GraphNode _first, _last; |
---|
| 776 | typedef std::deque<GraphEdge> Container; |
---|
| 777 | Container edges; |
---|
| 778 | |
---|
| 779 | public: |
---|
| 780 | |
---|
| 781 | DynamicPath(Graph &_G) : G(_G), _first(INVALID), _last(INVALID) {} |
---|
| 782 | |
---|
| 783 | /// Subpath defined by two nodes. |
---|
| 784 | /// Nodes may be in reversed order, then |
---|
| 785 | /// we contstruct the reversed path. |
---|
| 786 | DynamicPath(const DynamicPath &P, const NodeIt &a, const NodeIt &b); |
---|
| 787 | /// Subpath defined by two edges. Contains edges in [a,b) |
---|
| 788 | /// It is an error if the two edges are not in order! |
---|
| 789 | DynamicPath(const DynamicPath &P, const EdgeIt &a, const EdgeIt &b); |
---|
| 790 | |
---|
| 791 | size_t length() const { return edges.size(); } |
---|
| 792 | GraphNode from() const { return _first; } |
---|
| 793 | GraphNode to() const { return _last; } |
---|
| 794 | |
---|
| 795 | NodeIt& first(NodeIt &n) const { return nth(n, 0); } |
---|
| 796 | EdgeIt& first(EdgeIt &e) const { return nth(e, 0); } |
---|
| 797 | template<typename It> |
---|
| 798 | It first() const { |
---|
| 799 | It e; |
---|
| 800 | first(e); |
---|
| 801 | return e; |
---|
| 802 | } |
---|
| 803 | |
---|
| 804 | NodeIt& nth(NodeIt &, size_t) const; |
---|
| 805 | EdgeIt& nth(EdgeIt &, size_t) const; |
---|
| 806 | template<typename It> |
---|
| 807 | It nth(size_t n) const { |
---|
| 808 | It e; |
---|
| 809 | nth(e, n); |
---|
| 810 | return e; |
---|
| 811 | } |
---|
| 812 | |
---|
| 813 | bool valid(const NodeIt &n) const { return n.idx <= length(); } |
---|
| 814 | bool valid(const EdgeIt &e) const { return e.it < edges.end(); } |
---|
| 815 | |
---|
| 816 | bool isForward(const EdgeIt &e) const { return e.forw; } |
---|
| 817 | |
---|
| 818 | /// index of a node on the path. Returns length+2 for the invalid NodeIt |
---|
| 819 | int index(const NodeIt &n) const { return n.idx; } |
---|
| 820 | /// index of an edge on the path. Returns length+1 for the invalid EdgeIt |
---|
| 821 | int index(const EdgeIt &e) const { return e.it - edges.begin(); } |
---|
| 822 | |
---|
| 823 | EdgeIt& next(EdgeIt &e) const; |
---|
| 824 | NodeIt& next(NodeIt &n) const; |
---|
| 825 | template <typename It> |
---|
| 826 | It getNext(It it) const { |
---|
| 827 | It tmp(it); return next(tmp); |
---|
| 828 | } |
---|
| 829 | |
---|
| 830 | // A path is constructed using the following four functions. |
---|
| 831 | // They return false if the requested operation is inconsistent |
---|
| 832 | // with the path constructed so far. |
---|
| 833 | // If your path has only one edge you MUST set either "from" or "to"! |
---|
| 834 | // So you probably SHOULD call it in any case to be safe (and check the |
---|
| 835 | // returned value to check if your path is consistent with your idea). |
---|
| 836 | bool pushFront(const GraphEdge &e); |
---|
| 837 | bool pushBack(const GraphEdge &e); |
---|
| 838 | bool setFrom(const GraphNode &n); |
---|
| 839 | bool setTo(const GraphNode &n); |
---|
| 840 | |
---|
| 841 | // WARNING: these two functions return the head/tail of an edge with |
---|
| 842 | // respect to the direction of the path! |
---|
| 843 | // So G.head(P.graphEdge(e)) == P.graphNode(P.head(e)) holds only if |
---|
| 844 | // P.forward(e) is true (or the edge is a loop)! |
---|
| 845 | NodeIt head(const EdgeIt& e) const; |
---|
| 846 | NodeIt tail(const EdgeIt& e) const; |
---|
| 847 | |
---|
| 848 | // FIXME: ezeknek valami jobb nev kellene!!! |
---|
| 849 | GraphEdge graphEdge(const EdgeIt& e) const; |
---|
| 850 | GraphNode graphNode(const NodeIt& n) const; |
---|
| 851 | |
---|
| 852 | |
---|
| 853 | /*** Iterator classes ***/ |
---|
| 854 | class EdgeIt { |
---|
| 855 | friend class DynamicPath; |
---|
| 856 | |
---|
| 857 | typename Container::const_iterator it; |
---|
| 858 | bool forw; |
---|
| 859 | public: |
---|
| 860 | // FIXME: jarna neki ilyen is... |
---|
| 861 | // EdgeIt(Invalid); |
---|
| 862 | |
---|
| 863 | bool forward() const { return forw; } |
---|
| 864 | |
---|
| 865 | bool operator==(const EdgeIt& e) const { return it==e.it; } |
---|
| 866 | bool operator!=(const EdgeIt& e) const { return it!=e.it; } |
---|
| 867 | bool operator<(const EdgeIt& e) const { return it<e.it; } |
---|
| 868 | }; |
---|
| 869 | |
---|
| 870 | class NodeIt { |
---|
| 871 | friend class DynamicPath; |
---|
| 872 | |
---|
| 873 | size_t idx; |
---|
| 874 | bool tail; // Is this node the tail of the edge with same idx? |
---|
| 875 | |
---|
| 876 | public: |
---|
| 877 | // FIXME: jarna neki ilyen is... |
---|
| 878 | // NodeIt(Invalid); |
---|
| 879 | |
---|
| 880 | bool operator==(const NodeIt& n) const { return idx==n.idx; } |
---|
| 881 | bool operator!=(const NodeIt& n) const { return idx!=n.idx; } |
---|
| 882 | bool operator<(const NodeIt& n) const { return idx<n.idx; } |
---|
| 883 | }; |
---|
| 884 | |
---|
| 885 | private: |
---|
| 886 | bool edgeIncident(const GraphEdge &e, const GraphNode &a, |
---|
| 887 | GraphNode &b); |
---|
| 888 | bool connectTwoEdges(const GraphEdge &e, const GraphEdge &f); |
---|
| 889 | }; |
---|
| 890 | |
---|
| 891 | template<typename Gr> |
---|
| 892 | typename DynamicPath<Gr>::EdgeIt& |
---|
| 893 | DynamicPath<Gr>::next(DynamicPath::EdgeIt &e) const { |
---|
| 894 | if( e.it == edges.end() ) |
---|
| 895 | return e; |
---|
| 896 | |
---|
| 897 | GraphNode common_node = ( e.forw ? G.head(*e.it) : G.tail(*e.it) ); |
---|
| 898 | ++e.it; |
---|
| 899 | |
---|
| 900 | // Invalid edgeit is always forward :) |
---|
| 901 | if( e.it == edges.end() ) { |
---|
| 902 | e.forw = true; |
---|
| 903 | return e; |
---|
| 904 | } |
---|
| 905 | |
---|
| 906 | e.forw = ( G.tail(*e.it) == common_node ); |
---|
| 907 | return e; |
---|
| 908 | } |
---|
| 909 | |
---|
| 910 | template<typename Gr> |
---|
| 911 | typename DynamicPath<Gr>::NodeIt& DynamicPath<Gr>::next(NodeIt &n) const { |
---|
| 912 | if( n.idx >= length() ) { |
---|
| 913 | // FIXME: invalid |
---|
| 914 | n.idx = length()+1; |
---|
| 915 | return n; |
---|
| 916 | } |
---|
| 917 | |
---|
| 918 | |
---|
| 919 | GraphNode next_node = ( n.tail ? G.head(edges[n.idx]) : |
---|
| 920 | G.tail(edges[n.idx]) ); |
---|
| 921 | ++n.idx; |
---|
| 922 | if( n.idx < length() ) { |
---|
| 923 | n.tail = ( next_node == G.tail(edges[n.idx]) ); |
---|
| 924 | } |
---|
| 925 | else { |
---|
| 926 | n.tail = true; |
---|
| 927 | } |
---|
| 928 | |
---|
| 929 | return n; |
---|
| 930 | } |
---|
| 931 | |
---|
| 932 | template<typename Gr> |
---|
| 933 | bool DynamicPath<Gr>::edgeIncident(const GraphEdge &e, const GraphNode &a, |
---|
| 934 | GraphNode &b) { |
---|
| 935 | if( G.tail(e) == a ) { |
---|
| 936 | b=G.head(e); |
---|
| 937 | return true; |
---|
| 938 | } |
---|
| 939 | if( G.head(e) == a ) { |
---|
| 940 | b=G.tail(e); |
---|
| 941 | return true; |
---|
| 942 | } |
---|
| 943 | return false; |
---|
| 944 | } |
---|
| 945 | |
---|
| 946 | template<typename Gr> |
---|
| 947 | bool DynamicPath<Gr>::connectTwoEdges(const GraphEdge &e, |
---|
| 948 | const GraphEdge &f) { |
---|
| 949 | if( edgeIncident(f, G.tail(e), _last) ) { |
---|
| 950 | _first = G.head(e); |
---|
| 951 | return true; |
---|
| 952 | } |
---|
| 953 | if( edgeIncident(f, G.head(e), _last) ) { |
---|
| 954 | _first = G.tail(e); |
---|
| 955 | return true; |
---|
| 956 | } |
---|
| 957 | return false; |
---|
| 958 | } |
---|
| 959 | |
---|
| 960 | template<typename Gr> |
---|
| 961 | bool DynamicPath<Gr>::pushFront(const GraphEdge &e) { |
---|
| 962 | if( G.valid(_first) ) { |
---|
| 963 | if( edgeIncident(e, _first, _first) ) { |
---|
| 964 | edges.push_front(e); |
---|
| 965 | return true; |
---|
| 966 | } |
---|
| 967 | else |
---|
| 968 | return false; |
---|
| 969 | } |
---|
| 970 | else if( length() < 1 || connectTwoEdges(e, edges[0]) ) { |
---|
| 971 | edges.push_front(e); |
---|
| 972 | return true; |
---|
| 973 | } |
---|
| 974 | else |
---|
| 975 | return false; |
---|
| 976 | } |
---|
| 977 | |
---|
| 978 | template<typename Gr> |
---|
| 979 | bool DynamicPath<Gr>::pushBack(const GraphEdge &e) { |
---|
| 980 | if( G.valid(_last) ) { |
---|
| 981 | if( edgeIncident(e, _last, _last) ) { |
---|
| 982 | edges.push_back(e); |
---|
| 983 | return true; |
---|
| 984 | } |
---|
| 985 | else |
---|
| 986 | return false; |
---|
| 987 | } |
---|
| 988 | else if( length() < 1 || connectTwoEdges(edges[0], e) ) { |
---|
| 989 | edges.push_back(e); |
---|
| 990 | return true; |
---|
| 991 | } |
---|
| 992 | else |
---|
| 993 | return false; |
---|
| 994 | } |
---|
| 995 | |
---|
| 996 | |
---|
| 997 | template<typename Gr> |
---|
| 998 | bool DynamicPath<Gr>::setFrom(const GraphNode &n) { |
---|
| 999 | if( G.valid(_first) ) { |
---|
| 1000 | return _first == n; |
---|
| 1001 | } |
---|
| 1002 | else { |
---|
| 1003 | if( length() > 0) { |
---|
| 1004 | if( edgeIncident(edges[0], n, _last) ) { |
---|
| 1005 | _first = n; |
---|
| 1006 | return true; |
---|
| 1007 | } |
---|
| 1008 | else return false; |
---|
| 1009 | } |
---|
| 1010 | else { |
---|
| 1011 | _first = _last = n; |
---|
| 1012 | return true; |
---|
| 1013 | } |
---|
| 1014 | } |
---|
| 1015 | } |
---|
| 1016 | |
---|
| 1017 | template<typename Gr> |
---|
| 1018 | bool DynamicPath<Gr>::setTo(const GraphNode &n) { |
---|
| 1019 | if( G.valid(_last) ) { |
---|
| 1020 | return _last == n; |
---|
| 1021 | } |
---|
| 1022 | else { |
---|
| 1023 | if( length() > 0) { |
---|
| 1024 | if( edgeIncident(edges[0], n, _first) ) { |
---|
| 1025 | _last = n; |
---|
| 1026 | return true; |
---|
| 1027 | } |
---|
| 1028 | else return false; |
---|
| 1029 | } |
---|
| 1030 | else { |
---|
| 1031 | _first = _last = n; |
---|
| 1032 | return true; |
---|
| 1033 | } |
---|
| 1034 | } |
---|
| 1035 | } |
---|
| 1036 | |
---|
| 1037 | |
---|
| 1038 | template<typename Gr> |
---|
| 1039 | typename DynamicPath<Gr>::NodeIt |
---|
| 1040 | DynamicPath<Gr>::tail(const EdgeIt& e) const { |
---|
| 1041 | NodeIt n; |
---|
| 1042 | |
---|
| 1043 | if( e.it == edges.end() ) { |
---|
| 1044 | // FIXME: invalid-> invalid |
---|
| 1045 | n.idx = length() + 1; |
---|
| 1046 | n.tail = true; |
---|
| 1047 | return n; |
---|
| 1048 | } |
---|
| 1049 | |
---|
| 1050 | n.idx = e.it-edges.begin(); |
---|
| 1051 | n.tail = e.forw; |
---|
| 1052 | return n; |
---|
| 1053 | } |
---|
| 1054 | |
---|
| 1055 | template<typename Gr> |
---|
| 1056 | typename DynamicPath<Gr>::NodeIt |
---|
| 1057 | DynamicPath<Gr>::head(const EdgeIt& e) const { |
---|
| 1058 | if( e.it == edges.end()-1 ) { |
---|
| 1059 | return _last; |
---|
| 1060 | } |
---|
| 1061 | |
---|
| 1062 | EdgeIt next_edge = e; |
---|
| 1063 | next(next_edge); |
---|
| 1064 | return tail(next_edge); |
---|
| 1065 | } |
---|
| 1066 | |
---|
| 1067 | template<typename Gr> |
---|
| 1068 | typename DynamicPath<Gr>::GraphEdge |
---|
| 1069 | DynamicPath<Gr>::graphEdge(const EdgeIt& e) const { |
---|
| 1070 | if( e.it != edges.end() ) { |
---|
| 1071 | return *e.it; |
---|
| 1072 | } |
---|
| 1073 | else { |
---|
| 1074 | return INVALID; |
---|
| 1075 | } |
---|
| 1076 | } |
---|
| 1077 | |
---|
| 1078 | template<typename Gr> |
---|
| 1079 | typename DynamicPath<Gr>::GraphNode |
---|
| 1080 | DynamicPath<Gr>::graphNode(const NodeIt& n) const { |
---|
| 1081 | if( n.idx < length() ) { |
---|
| 1082 | return n.tail ? G.tail(edges[n.idx]) : G.head(edges[n.idx]); |
---|
| 1083 | } |
---|
| 1084 | else if( n.idx == length() ) { |
---|
| 1085 | return _last; |
---|
| 1086 | } |
---|
| 1087 | else { |
---|
| 1088 | return INVALID; |
---|
| 1089 | } |
---|
| 1090 | } |
---|
| 1091 | |
---|
| 1092 | template<typename Gr> |
---|
| 1093 | typename DynamicPath<Gr>::EdgeIt& |
---|
| 1094 | DynamicPath<Gr>::nth(EdgeIt &e, size_t k) const { |
---|
| 1095 | if( k>=length() ) { |
---|
| 1096 | // FIXME: invalid EdgeIt |
---|
| 1097 | e.it = edges.end(); |
---|
| 1098 | e.forw = true; |
---|
| 1099 | return e; |
---|
| 1100 | } |
---|
| 1101 | |
---|
| 1102 | e.it = edges.begin()+k; |
---|
| 1103 | if(k==0) { |
---|
| 1104 | e.forw = ( G.tail(*e.it) == _first ); |
---|
| 1105 | } |
---|
| 1106 | else { |
---|
| 1107 | e.forw = ( G.tail(*e.it) == G.tail(edges[k-1]) || |
---|
| 1108 | G.tail(*e.it) == G.head(edges[k-1]) ); |
---|
| 1109 | } |
---|
| 1110 | return e; |
---|
| 1111 | } |
---|
| 1112 | |
---|
| 1113 | template<typename Gr> |
---|
| 1114 | typename DynamicPath<Gr>::NodeIt& |
---|
| 1115 | DynamicPath<Gr>::nth(NodeIt &n, size_t k) const { |
---|
| 1116 | if( k>length() ) { |
---|
| 1117 | // FIXME: invalid NodeIt |
---|
| 1118 | n.idx = length()+1; |
---|
| 1119 | n.tail = true; |
---|
| 1120 | return n; |
---|
| 1121 | } |
---|
| 1122 | if( k==length() ) { |
---|
| 1123 | n.idx = length(); |
---|
| 1124 | n.tail = true; |
---|
| 1125 | return n; |
---|
| 1126 | } |
---|
| 1127 | n = tail(nth<EdgeIt>(k)); |
---|
| 1128 | return n; |
---|
| 1129 | } |
---|
| 1130 | |
---|
| 1131 | // Reszut konstruktorok: |
---|
| 1132 | |
---|
| 1133 | |
---|
| 1134 | template<typename Gr> |
---|
| 1135 | DynamicPath<Gr>::DynamicPath(const DynamicPath &P, const EdgeIt &a, |
---|
| 1136 | const EdgeIt &b) : |
---|
| 1137 | G(P.G), edges(a.it, b.it) // WARNING: if b.it < a.it this will blow up! |
---|
| 1138 | { |
---|
| 1139 | if( G.valid(P._first) && a.it < P.edges.end() ) { |
---|
| 1140 | _first = ( a.forw ? G.tail(*a.it) : G.head(*a.it) ); |
---|
| 1141 | if( b.it < P.edges.end() ) { |
---|
| 1142 | _last = ( b.forw ? G.tail(*b.it) : G.head(*b.it) ); |
---|
| 1143 | } |
---|
| 1144 | else { |
---|
| 1145 | _last = P._last; |
---|
| 1146 | } |
---|
| 1147 | } |
---|
| 1148 | } |
---|
| 1149 | |
---|
| 1150 | template<typename Gr> |
---|
| 1151 | DynamicPath<Gr>::DynamicPath(const DynamicPath &P, const NodeIt &a, |
---|
| 1152 | const NodeIt &b) : G(P.G) |
---|
| 1153 | { |
---|
| 1154 | if( !P.valid(a) || !P.valid(b) ) |
---|
| 1155 | return; |
---|
| 1156 | |
---|
| 1157 | int ai = a.idx, bi = b.idx; |
---|
| 1158 | if( bi<ai ) |
---|
| 1159 | std::swap(ai,bi); |
---|
| 1160 | |
---|
| 1161 | edges.resize(bi-ai); |
---|
| 1162 | copy(P.edges.begin()+ai, P.edges.begin()+bi, edges.begin()); |
---|
| 1163 | |
---|
| 1164 | _first = P.graphNode(a); |
---|
| 1165 | _last = P.graphNode(b); |
---|
| 1166 | } |
---|
| 1167 | |
---|
| 1168 | ///@} |
---|
| 1169 | |
---|
| 1170 | } // namespace hugo |
---|
| 1171 | |
---|
| 1172 | #endif // HUGO_PATH_H |
---|