[797] | 1 | // -*- c++ -*- // |
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| 2 | |
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[807] | 3 | ///\ingroup skeletons |
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[797] | 4 | ///\file |
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| 5 | ///\brief Classes for representing paths in graphs. |
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| 6 | |
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| 7 | #ifndef HUGO_PATH_H |
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| 8 | #define HUGO_PATH_H |
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| 9 | |
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| 10 | #include <hugo/invalid.h> |
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| 11 | |
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| 12 | namespace hugo { |
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[803] | 13 | namespace skeleton { |
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| 14 | /// \addtogroup skeletons |
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| 15 | /// @{ |
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| 16 | |
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| 17 | |
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[806] | 18 | //! \brief A skeletom structure for representing directed paths in a graph. |
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[803] | 19 | //! |
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[806] | 20 | //! A skeleton structure for representing directed paths in a graph. |
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[803] | 21 | //! \param GR The graph type in which the path is. |
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| 22 | //! |
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| 23 | //! In a sense, the path can be treated as a graph, for is has \c NodeIt |
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| 24 | //! and \c EdgeIt with the same usage. These types converts to the \c Node |
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| 25 | //! and \c Edge of the original graph. |
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| 26 | template<typename GR> |
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| 27 | class Path { |
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| 28 | public: |
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| 29 | |
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| 30 | /// Type of the underlying graph. |
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| 31 | typedef typename GR Graph; |
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| 32 | /// Edge type of the underlying graph. |
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| 33 | typedef typename Graph::Edge GraphEdge; |
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| 34 | /// Node type of the underlying graph. |
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| 35 | typedef typename Graph::Node GraphNode; |
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| 36 | class NodeIt; |
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| 37 | class EdgeIt; |
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| 38 | |
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| 39 | /// \param _G The graph in which the path is. |
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| 40 | /// |
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| 41 | Path(const Graph &_G) {} |
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| 42 | |
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| 43 | /// Length of the path. |
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| 44 | size_t length() const {} |
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| 45 | /// Returns whether the path is empty. |
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| 46 | bool empty() const {} |
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| 47 | |
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| 48 | /// Resets the path to an empty path. |
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| 49 | void clear() {} |
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[797] | 50 | |
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[803] | 51 | /// \brief Starting point of the path. |
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| 52 | /// |
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| 53 | /// Starting point of the path. |
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| 54 | /// Returns INVALID if the path is empty. |
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| 55 | NodeIt head() const {} |
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| 56 | /// \brief End point of the path. |
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| 57 | /// |
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| 58 | /// End point of the path. |
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| 59 | /// Returns INVALID if the path is empty. |
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| 60 | NodeIt tail() const {} |
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[797] | 61 | |
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[803] | 62 | /// \brief First NodeIt/EdgeIt. |
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| 63 | /// |
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| 64 | /// Initializes node or edge iterator to point to the first |
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| 65 | /// node or edge. |
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| 66 | template<typename It> |
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| 67 | It& first(It &i) const { return i=It(*this); } |
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[797] | 68 | |
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[803] | 69 | /// \brief The head of an edge. |
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| 70 | /// |
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| 71 | /// Returns node iterator pointing to the head node of the |
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| 72 | /// given edge iterator. |
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| 73 | NodeIt head(const EdgeIt& e) const {} |
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[797] | 74 | |
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[803] | 75 | /// \brief The tail of an edge. |
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| 76 | /// |
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| 77 | /// Returns node iterator pointing to the tail node of the |
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| 78 | /// given edge iterator. |
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| 79 | NodeIt tail(const EdgeIt& e) const {} |
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[797] | 80 | |
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| 81 | |
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[803] | 82 | /* Iterator classes */ |
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[797] | 83 | |
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[803] | 84 | /** |
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| 85 | * \brief Iterator class to iterate on the edges of the paths |
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| 86 | * |
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| 87 | * \ingroup skeletons |
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| 88 | * This class is used to iterate on the edges of the paths |
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| 89 | * |
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| 90 | * Of course it converts to Graph::Edge |
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| 91 | * |
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| 92 | */ |
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| 93 | class EdgeIt { |
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| 94 | public: |
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| 95 | /// Default constructor |
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| 96 | EdgeIt() {} |
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| 97 | /// Invalid constructor |
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| 98 | EdgeIt(Invalid) {} |
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| 99 | /// Constructor with starting point |
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| 100 | EdgeIt(const Path &_p) {} |
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[797] | 101 | |
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[803] | 102 | operator GraphEdge () const {} |
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[797] | 103 | |
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[803] | 104 | /// Next edge |
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| 105 | EdgeIt& operator++() {} |
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[797] | 106 | |
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[803] | 107 | /// Comparison operator |
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| 108 | bool operator==(const EdgeIt& e) const {} |
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| 109 | /// Comparison operator |
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| 110 | bool operator!=(const EdgeIt& e) const {} |
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| 111 | // /// Comparison operator |
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| 112 | // /// \todo It is not clear what is the "natural" ordering. |
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| 113 | // bool operator<(const EdgeIt& e) const {} |
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[797] | 114 | |
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[803] | 115 | }; |
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[797] | 116 | |
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[803] | 117 | /** |
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| 118 | * \brief Iterator class to iterate on the nodes of the paths |
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| 119 | * |
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| 120 | * \ingroup skeletons |
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| 121 | * This class is used to iterate on the nodes of the paths |
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| 122 | * |
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| 123 | * Of course it converts to Graph::Node. |
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| 124 | * |
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| 125 | */ |
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| 126 | class NodeIt { |
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| 127 | public: |
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| 128 | /// Default constructor |
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| 129 | NodeIt() {} |
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| 130 | /// Invalid constructor |
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| 131 | NodeIt(Invalid) {} |
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| 132 | /// Constructor with starting point |
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| 133 | NodeIt(const Path &_p) {} |
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[797] | 134 | |
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[803] | 135 | ///Conversion to Graph::Node |
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| 136 | operator const GraphNode& () const {} |
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| 137 | /// Next node |
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| 138 | NodeIt& operator++() {} |
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[797] | 139 | |
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[803] | 140 | /// Comparison operator |
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| 141 | bool operator==(const NodeIt& e) const {} |
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| 142 | /// Comparison operator |
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| 143 | bool operator!=(const NodeIt& e) const {} |
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| 144 | // /// Comparison operator |
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| 145 | // /// \todo It is not clear what is the "natural" ordering. |
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| 146 | // bool operator<(const NodeIt& e) const {} |
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[797] | 147 | |
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[803] | 148 | }; |
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[797] | 149 | |
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[803] | 150 | friend class Builder; |
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[797] | 151 | |
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[803] | 152 | /** |
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| 153 | * \brief Class to build paths |
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| 154 | * |
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| 155 | * \ingroup skeletons |
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| 156 | * This class is used to fill a path with edges. |
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| 157 | * |
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| 158 | * You can push new edges to the front and to the back of the path in |
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| 159 | * arbitrary order then you should commit these changes to the graph. |
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| 160 | * |
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| 161 | * While the builder is active (after the first modifying |
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| 162 | * operation and until the call of \ref commit()) |
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| 163 | * the underlining Path is in a |
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| 164 | * "transitional" state (operations on it have undefined result). |
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| 165 | */ |
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| 166 | class Builder { |
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| 167 | public: |
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| 168 | ///\param _P the path you want to fill in. |
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| 169 | /// |
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| 170 | Builder(Path &_P) : P(_P) {} |
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[797] | 171 | |
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[803] | 172 | /// Sets the starting node of the path. |
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| 173 | |
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| 174 | /// Sets the starting node of the path. Edge added to the path |
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| 175 | /// afterwards have to be incident to this node. |
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| 176 | /// You \em must start building an empry path with this functions. |
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| 177 | /// (And you \em must \em not use it later). |
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| 178 | /// \sa pushFront() |
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| 179 | /// \sa pushBack() |
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| 180 | void setStartNode(const GraphNode &) {} |
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[797] | 181 | |
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[803] | 182 | ///Push a new edge to the front of the path |
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[797] | 183 | |
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[803] | 184 | ///Push a new edge to the front of the path. |
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| 185 | ///If the path is empty, you \em must call \ref setStartNode() before |
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| 186 | ///the first use of \ref pushFront(). |
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| 187 | void pushFront(const GraphEdge& e) {} |
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[797] | 188 | |
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[803] | 189 | ///Push a new edge to the back of the path |
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[797] | 190 | |
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[803] | 191 | ///Push a new edge to the back of the path. |
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| 192 | ///If the path is empty, you \em must call \ref setStartNode() before |
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| 193 | ///the first use of \ref pushBack(). |
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| 194 | void pushBack(const GraphEdge& e) {} |
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[797] | 195 | |
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[803] | 196 | ///Commit the changes to the path. |
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| 197 | void commit() {} |
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[797] | 198 | |
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[803] | 199 | ///Reserve (front) storage for the builder in advance. |
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[797] | 200 | |
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[803] | 201 | ///If you know an reasonable upper bound of the number of the edges |
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| 202 | ///to add to the front of the path, |
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| 203 | ///using this function you may speed up the building. |
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| 204 | void reserveFront(size_t r) {} |
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| 205 | ///Reserve (back) storage for the builder in advance. |
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[797] | 206 | |
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[803] | 207 | ///If you know an reasonable upper bound of the number of the edges |
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| 208 | ///to add to the back of the path, |
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| 209 | ///using this function you may speed up the building. |
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| 210 | void reserveBack(size_t r) {} |
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| 211 | }; |
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[797] | 212 | }; |
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| 213 | |
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[803] | 214 | ///@} |
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[797] | 215 | } |
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| 216 | |
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| 217 | } // namespace hugo |
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| 218 | |
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| 219 | #endif // HUGO_PATH_H |
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