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