[209] | 1 | /* -*- mode: C++; indent-tabs-mode: nil; -*- |
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[96] | 2 | * |
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[209] | 3 | * This file is a part of LEMON, a generic C++ optimization library. |
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[96] | 4 | * |
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[1270] | 5 | * Copyright (C) 2003-2013 |
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[96] | 6 | * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
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| 7 | * (Egervary Research Group on Combinatorial Optimization, EGRES). |
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| 8 | * |
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| 9 | * Permission to use, modify and distribute this software is granted |
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| 10 | * provided that this copyright notice appears in all copies. For |
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| 11 | * precise terms see the accompanying LICENSE file. |
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| 12 | * |
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| 13 | * This software is provided "AS IS" with no warranty of any kind, |
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| 14 | * express or implied, and with no claim as to its suitability for any |
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| 15 | * purpose. |
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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 digraphs. |
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| 22 | /// |
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| 23 | |
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| 24 | #ifndef LEMON_PATH_H |
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| 25 | #define LEMON_PATH_H |
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| 26 | |
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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 <lemon/error.h> |
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[220] | 31 | #include <lemon/core.h> |
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[100] | 32 | #include <lemon/concepts/path.h> |
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[1336] | 33 | #include <lemon/bits/stl_iterators.h> |
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[96] | 34 | |
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| 35 | namespace lemon { |
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| 36 | |
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| 37 | /// \addtogroup paths |
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| 38 | /// @{ |
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| 39 | |
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| 40 | |
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| 41 | /// \brief A structure for representing directed paths in a digraph. |
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| 42 | /// |
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| 43 | /// A structure for representing directed path in a digraph. |
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[606] | 44 | /// \tparam GR The digraph type in which the path is. |
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[96] | 45 | /// |
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[1420] | 46 | /// In a sense, a path can be treated as a list of arcs. The |
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| 47 | /// LEMON path type simply stores this list. As a consequence, it |
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| 48 | /// cannot enumerate the nodes in the path, and the source node of |
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| 49 | /// a zero-length path is undefined. |
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[96] | 50 | /// |
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| 51 | /// This implementation is a back and front insertable and erasable |
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| 52 | /// path type. It can be indexed in O(1) time. The front and back |
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[97] | 53 | /// insertion and erase is done in O(1) (amortized) time. The |
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| 54 | /// implementation uses two vectors for storing the front and back |
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| 55 | /// insertions. |
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[606] | 56 | template <typename GR> |
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[96] | 57 | class Path { |
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| 58 | public: |
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| 59 | |
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[606] | 60 | typedef GR Digraph; |
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[96] | 61 | typedef typename Digraph::Arc Arc; |
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| 62 | |
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| 63 | /// \brief Default constructor |
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| 64 | /// |
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| 65 | /// Default constructor |
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| 66 | Path() {} |
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| 67 | |
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[1144] | 68 | /// \brief Copy constructor |
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| 69 | /// |
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| 70 | Path(const Path& cpath) { |
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| 71 | pathCopy(cpath, *this); |
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| 72 | } |
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| 73 | |
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[96] | 74 | /// \brief Template copy constructor |
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| 75 | /// |
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[97] | 76 | /// This constuctor initializes the path from any other path type. |
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| 77 | /// It simply makes a copy of the given path. |
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[96] | 78 | template <typename CPath> |
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| 79 | Path(const CPath& cpath) { |
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[551] | 80 | pathCopy(cpath, *this); |
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[96] | 81 | } |
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| 82 | |
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[1144] | 83 | /// \brief Copy assignment |
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| 84 | /// |
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| 85 | Path& operator=(const Path& cpath) { |
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| 86 | pathCopy(cpath, *this); |
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| 87 | return *this; |
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| 88 | } |
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| 89 | |
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[96] | 90 | /// \brief Template copy assignment |
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| 91 | /// |
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[97] | 92 | /// This operator makes a copy of a path of any other type. |
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[96] | 93 | template <typename CPath> |
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| 94 | Path& operator=(const CPath& cpath) { |
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[551] | 95 | pathCopy(cpath, *this); |
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[96] | 96 | return *this; |
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| 97 | } |
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| 98 | |
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[236] | 99 | /// \brief LEMON style iterator for path arcs |
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[96] | 100 | /// |
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| 101 | /// This class is used to iterate on the arcs of the paths. |
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| 102 | class ArcIt { |
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| 103 | friend class Path; |
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| 104 | public: |
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| 105 | /// \brief Default constructor |
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| 106 | ArcIt() {} |
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| 107 | /// \brief Invalid constructor |
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| 108 | ArcIt(Invalid) : path(0), idx(-1) {} |
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[97] | 109 | /// \brief Initializate the iterator to the first arc of path |
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[209] | 110 | ArcIt(const Path &_path) |
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[96] | 111 | : path(&_path), idx(_path.empty() ? -1 : 0) {} |
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| 112 | |
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| 113 | private: |
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| 114 | |
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[209] | 115 | ArcIt(const Path &_path, int _idx) |
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[96] | 116 | : path(&_path), idx(_idx) {} |
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| 117 | |
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| 118 | public: |
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| 119 | |
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| 120 | /// \brief Conversion to Arc |
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| 121 | operator const Arc&() const { |
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| 122 | return path->nth(idx); |
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| 123 | } |
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| 124 | |
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| 125 | /// \brief Next arc |
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[209] | 126 | ArcIt& operator++() { |
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[96] | 127 | ++idx; |
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[209] | 128 | if (idx >= path->length()) idx = -1; |
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| 129 | return *this; |
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[96] | 130 | } |
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| 131 | |
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| 132 | /// \brief Comparison operator |
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| 133 | bool operator==(const ArcIt& e) const { return idx==e.idx; } |
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| 134 | /// \brief Comparison operator |
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| 135 | bool operator!=(const ArcIt& e) const { return idx!=e.idx; } |
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| 136 | /// \brief Comparison operator |
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| 137 | bool operator<(const ArcIt& e) const { return idx<e.idx; } |
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| 138 | |
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| 139 | private: |
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| 140 | const Path *path; |
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| 141 | int idx; |
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| 142 | }; |
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| 143 | |
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[1336] | 144 | /// \brief Gets the collection of the arcs of the path. |
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| 145 | /// |
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| 146 | /// This function can be used for iterating on the |
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| 147 | /// arcs of the path. It returns a wrapped |
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| 148 | /// ArcIt, which looks like an STL container |
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| 149 | /// (by having begin() and end()) which you can use in range-based |
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| 150 | /// for loops, STL algorithms, etc. |
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| 151 | /// For example you can write: |
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| 152 | ///\code |
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| 153 | /// for(auto a: p.arcs()) |
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| 154 | /// doSomething(a); |
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| 155 | ///\endcode |
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| 156 | LemonRangeWrapper1<ArcIt, Path> arcs() const { |
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| 157 | return LemonRangeWrapper1<ArcIt, Path>(*this); |
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| 158 | } |
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| 159 | |
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| 160 | |
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[96] | 161 | /// \brief Length of the path. |
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| 162 | int length() const { return head.size() + tail.size(); } |
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[97] | 163 | /// \brief Return whether the path is empty. |
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[96] | 164 | bool empty() const { return head.empty() && tail.empty(); } |
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| 165 | |
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[97] | 166 | /// \brief Reset the path to an empty one. |
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[96] | 167 | void clear() { head.clear(); tail.clear(); } |
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| 168 | |
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[1024] | 169 | /// \brief The n-th arc. |
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[96] | 170 | /// |
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[1420] | 171 | /// Gives back the n-th arc. This function runs in O(1) time. |
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| 172 | /// \pre \c n is in the range <tt>[0..length() - 1]</tt>. |
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[96] | 173 | const Arc& nth(int n) const { |
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| 174 | return n < int(head.size()) ? *(head.rbegin() + n) : |
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| 175 | *(tail.begin() + (n - head.size())); |
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| 176 | } |
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| 177 | |
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[1024] | 178 | /// \brief Initialize arc iterator to point to the n-th arc |
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[96] | 179 | /// |
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[606] | 180 | /// \pre \c n is in the <tt>[0..length() - 1]</tt> range. |
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[96] | 181 | ArcIt nthIt(int n) const { |
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| 182 | return ArcIt(*this, n); |
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| 183 | } |
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| 184 | |
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[1421] | 185 | /// \brief The n-th arc. |
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| 186 | /// |
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| 187 | /// Gives back the n-th arc. This operator is just an alias for \ref nth(), |
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| 188 | /// it runs in O(1) time. |
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| 189 | /// \pre \c n is in the range <tt>[0..length() - 1]</tt>. |
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| 190 | const Arc& operator[](int n) const { |
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| 191 | return nth(n); |
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| 192 | } |
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| 193 | |
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[97] | 194 | /// \brief The first arc of the path |
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[96] | 195 | const Arc& front() const { |
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| 196 | return head.empty() ? tail.front() : head.back(); |
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| 197 | } |
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| 198 | |
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| 199 | /// \brief Add a new arc before the current path |
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| 200 | void addFront(const Arc& arc) { |
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| 201 | head.push_back(arc); |
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| 202 | } |
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| 203 | |
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| 204 | /// \brief Erase the first arc of the path |
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| 205 | void eraseFront() { |
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| 206 | if (!head.empty()) { |
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| 207 | head.pop_back(); |
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| 208 | } else { |
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| 209 | head.clear(); |
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| 210 | int halfsize = tail.size() / 2; |
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| 211 | head.resize(halfsize); |
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| 212 | std::copy(tail.begin() + 1, tail.begin() + halfsize + 1, |
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| 213 | head.rbegin()); |
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| 214 | std::copy(tail.begin() + halfsize + 1, tail.end(), tail.begin()); |
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| 215 | tail.resize(tail.size() - halfsize - 1); |
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| 216 | } |
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| 217 | } |
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| 218 | |
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[97] | 219 | /// \brief The last arc of the path |
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[96] | 220 | const Arc& back() const { |
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| 221 | return tail.empty() ? head.front() : tail.back(); |
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| 222 | } |
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| 223 | |
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| 224 | /// \brief Add a new arc behind the current path |
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| 225 | void addBack(const Arc& arc) { |
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| 226 | tail.push_back(arc); |
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| 227 | } |
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| 228 | |
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| 229 | /// \brief Erase the last arc of the path |
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| 230 | void eraseBack() { |
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| 231 | if (!tail.empty()) { |
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| 232 | tail.pop_back(); |
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| 233 | } else { |
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| 234 | int halfsize = head.size() / 2; |
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| 235 | tail.resize(halfsize); |
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| 236 | std::copy(head.begin() + 1, head.begin() + halfsize + 1, |
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| 237 | tail.rbegin()); |
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| 238 | std::copy(head.begin() + halfsize + 1, head.end(), head.begin()); |
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| 239 | head.resize(head.size() - halfsize - 1); |
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| 240 | } |
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| 241 | } |
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| 242 | |
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| 243 | typedef True BuildTag; |
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| 244 | |
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| 245 | template <typename CPath> |
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| 246 | void build(const CPath& path) { |
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| 247 | int len = path.length(); |
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| 248 | tail.reserve(len); |
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| 249 | for (typename CPath::ArcIt it(path); it != INVALID; ++it) { |
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| 250 | tail.push_back(it); |
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| 251 | } |
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| 252 | } |
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| 253 | |
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| 254 | template <typename CPath> |
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| 255 | void buildRev(const CPath& path) { |
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| 256 | int len = path.length(); |
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| 257 | head.reserve(len); |
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| 258 | for (typename CPath::RevArcIt it(path); it != INVALID; ++it) { |
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| 259 | head.push_back(it); |
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| 260 | } |
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| 261 | } |
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| 262 | |
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| 263 | protected: |
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| 264 | typedef std::vector<Arc> Container; |
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| 265 | Container head, tail; |
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| 266 | |
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| 267 | }; |
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| 268 | |
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| 269 | /// \brief A structure for representing directed paths in a digraph. |
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| 270 | /// |
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| 271 | /// A structure for representing directed path in a digraph. |
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[606] | 272 | /// \tparam GR The digraph type in which the path is. |
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[96] | 273 | /// |
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[1420] | 274 | /// In a sense, a path can be treated as a list of arcs. The |
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| 275 | /// LEMON path type simply stores this list. As a consequence, it |
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| 276 | /// cannot enumerate the nodes in the path, and the source node of |
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| 277 | /// a zero-length path is undefined. |
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[96] | 278 | /// |
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| 279 | /// This implementation is a just back insertable and erasable path |
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| 280 | /// type. It can be indexed in O(1) time. The back insertion and |
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| 281 | /// erasure is amortized O(1) time. This implementation is faster |
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[1420] | 282 | /// than the \c Path type because it use just one vector for the |
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[96] | 283 | /// arcs. |
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[606] | 284 | template <typename GR> |
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[96] | 285 | class SimplePath { |
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| 286 | public: |
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| 287 | |
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[606] | 288 | typedef GR Digraph; |
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[96] | 289 | typedef typename Digraph::Arc Arc; |
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| 290 | |
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| 291 | /// \brief Default constructor |
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| 292 | /// |
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| 293 | /// Default constructor |
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| 294 | SimplePath() {} |
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| 295 | |
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[1144] | 296 | /// \brief Copy constructor |
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| 297 | /// |
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| 298 | SimplePath(const SimplePath& cpath) { |
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| 299 | pathCopy(cpath, *this); |
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| 300 | } |
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| 301 | |
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[96] | 302 | /// \brief Template copy constructor |
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| 303 | /// |
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| 304 | /// This path can be initialized with any other path type. It just |
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| 305 | /// makes a copy of the given path. |
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| 306 | template <typename CPath> |
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| 307 | SimplePath(const CPath& cpath) { |
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[551] | 308 | pathCopy(cpath, *this); |
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[96] | 309 | } |
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| 310 | |
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[1144] | 311 | /// \brief Copy assignment |
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| 312 | /// |
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| 313 | SimplePath& operator=(const SimplePath& cpath) { |
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| 314 | pathCopy(cpath, *this); |
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| 315 | return *this; |
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| 316 | } |
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| 317 | |
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[96] | 318 | /// \brief Template copy assignment |
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| 319 | /// |
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| 320 | /// This path can be initialized with any other path type. It just |
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| 321 | /// makes a copy of the given path. |
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| 322 | template <typename CPath> |
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| 323 | SimplePath& operator=(const CPath& cpath) { |
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[551] | 324 | pathCopy(cpath, *this); |
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[96] | 325 | return *this; |
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| 326 | } |
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| 327 | |
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| 328 | /// \brief Iterator class to iterate on the arcs of the paths |
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| 329 | /// |
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| 330 | /// This class is used to iterate on the arcs of the paths |
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| 331 | /// |
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| 332 | /// Of course it converts to Digraph::Arc |
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| 333 | class ArcIt { |
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| 334 | friend class SimplePath; |
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| 335 | public: |
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| 336 | /// Default constructor |
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| 337 | ArcIt() {} |
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| 338 | /// Invalid constructor |
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| 339 | ArcIt(Invalid) : path(0), idx(-1) {} |
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| 340 | /// \brief Initializate the constructor to the first arc of path |
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[209] | 341 | ArcIt(const SimplePath &_path) |
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[96] | 342 | : path(&_path), idx(_path.empty() ? -1 : 0) {} |
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| 343 | |
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| 344 | private: |
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| 345 | |
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| 346 | /// Constructor with starting point |
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[209] | 347 | ArcIt(const SimplePath &_path, int _idx) |
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[1212] | 348 | : path(&_path), idx(_idx) {} |
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[96] | 349 | |
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| 350 | public: |
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| 351 | |
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| 352 | ///Conversion to Digraph::Arc |
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| 353 | operator const Arc&() const { |
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| 354 | return path->nth(idx); |
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| 355 | } |
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| 356 | |
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| 357 | /// Next arc |
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[209] | 358 | ArcIt& operator++() { |
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[96] | 359 | ++idx; |
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[209] | 360 | if (idx >= path->length()) idx = -1; |
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| 361 | return *this; |
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[96] | 362 | } |
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| 363 | |
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| 364 | /// Comparison operator |
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| 365 | bool operator==(const ArcIt& e) const { return idx==e.idx; } |
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| 366 | /// Comparison operator |
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| 367 | bool operator!=(const ArcIt& e) const { return idx!=e.idx; } |
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| 368 | /// Comparison operator |
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| 369 | bool operator<(const ArcIt& e) const { return idx<e.idx; } |
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| 370 | |
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| 371 | private: |
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| 372 | const SimplePath *path; |
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| 373 | int idx; |
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| 374 | }; |
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| 375 | |
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[1336] | 376 | /// \brief Gets the collection of the arcs of the path. |
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| 377 | /// |
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| 378 | /// This function can be used for iterating on the |
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| 379 | /// arcs of the path. It returns a wrapped |
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| 380 | /// ArcIt, which looks like an STL container |
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| 381 | /// (by having begin() and end()) which you can use in range-based |
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| 382 | /// for loops, STL algorithms, etc. |
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| 383 | /// For example you can write: |
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| 384 | ///\code |
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| 385 | /// for(auto a: p.arcs()) |
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| 386 | /// doSomething(a); |
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| 387 | ///\endcode |
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| 388 | LemonRangeWrapper1<ArcIt, SimplePath> arcs() const { |
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| 389 | return LemonRangeWrapper1<ArcIt, SimplePath>(*this); |
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| 390 | } |
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| 391 | |
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| 392 | |
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[96] | 393 | /// \brief Length of the path. |
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| 394 | int length() const { return data.size(); } |
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[97] | 395 | /// \brief Return true if the path is empty. |
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[96] | 396 | bool empty() const { return data.empty(); } |
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| 397 | |
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[97] | 398 | /// \brief Reset the path to an empty one. |
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[96] | 399 | void clear() { data.clear(); } |
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| 400 | |
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[1024] | 401 | /// \brief The n-th arc. |
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[96] | 402 | /// |
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[1420] | 403 | /// Gives back the n-th arc. This function runs in O(1) time. |
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| 404 | /// \pre \c n is in the range <tt>[0..length() - 1]</tt>. |
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[96] | 405 | const Arc& nth(int n) const { |
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| 406 | return data[n]; |
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| 407 | } |
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| 408 | |
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[1024] | 409 | /// \brief Initializes arc iterator to point to the n-th arc. |
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[96] | 410 | ArcIt nthIt(int n) const { |
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| 411 | return ArcIt(*this, n); |
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| 412 | } |
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| 413 | |
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[1421] | 414 | /// \brief The n-th arc. |
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| 415 | /// |
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| 416 | /// Gives back the n-th arc. This operator is just an alias for \ref nth(), |
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| 417 | /// it runs in O(1) time. |
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| 418 | /// \pre \c n is in the range <tt>[0..length() - 1]</tt>. |
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| 419 | const Arc& operator[](int n) const { |
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| 420 | return data[n]; |
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| 421 | } |
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| 422 | |
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[97] | 423 | /// \brief The first arc of the path. |
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[96] | 424 | const Arc& front() const { |
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| 425 | return data.front(); |
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| 426 | } |
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| 427 | |
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[97] | 428 | /// \brief The last arc of the path. |
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[96] | 429 | const Arc& back() const { |
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| 430 | return data.back(); |
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| 431 | } |
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| 432 | |
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| 433 | /// \brief Add a new arc behind the current path. |
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| 434 | void addBack(const Arc& arc) { |
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| 435 | data.push_back(arc); |
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| 436 | } |
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| 437 | |
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| 438 | /// \brief Erase the last arc of the path |
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| 439 | void eraseBack() { |
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| 440 | data.pop_back(); |
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| 441 | } |
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| 442 | |
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| 443 | typedef True BuildTag; |
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| 444 | |
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| 445 | template <typename CPath> |
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| 446 | void build(const CPath& path) { |
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| 447 | int len = path.length(); |
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| 448 | data.resize(len); |
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| 449 | int index = 0; |
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| 450 | for (typename CPath::ArcIt it(path); it != INVALID; ++it) { |
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| 451 | data[index] = it;; |
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| 452 | ++index; |
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| 453 | } |
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| 454 | } |
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| 455 | |
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| 456 | template <typename CPath> |
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| 457 | void buildRev(const CPath& path) { |
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| 458 | int len = path.length(); |
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| 459 | data.resize(len); |
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| 460 | int index = len; |
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| 461 | for (typename CPath::RevArcIt it(path); it != INVALID; ++it) { |
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| 462 | --index; |
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| 463 | data[index] = it;; |
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| 464 | } |
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| 465 | } |
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| 466 | |
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| 467 | protected: |
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| 468 | typedef std::vector<Arc> Container; |
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| 469 | Container data; |
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| 470 | |
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| 471 | }; |
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| 472 | |
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| 473 | /// \brief A structure for representing directed paths in a digraph. |
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| 474 | /// |
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| 475 | /// A structure for representing directed path in a digraph. |
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[606] | 476 | /// \tparam GR The digraph type in which the path is. |
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[96] | 477 | /// |
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[1420] | 478 | /// In a sense, a path can be treated as a list of arcs. The |
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| 479 | /// LEMON path type simply stores this list. As a consequence, it |
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| 480 | /// cannot enumerate the nodes in the path, and the source node of |
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| 481 | /// a zero-length path is undefined. |
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[96] | 482 | /// |
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| 483 | /// This implementation is a back and front insertable and erasable |
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| 484 | /// path type. It can be indexed in O(k) time, where k is the rank |
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| 485 | /// of the arc in the path. The length can be computed in O(n) |
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| 486 | /// time. The front and back insertion and erasure is O(1) time |
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| 487 | /// and it can be splited and spliced in O(1) time. |
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[606] | 488 | template <typename GR> |
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[96] | 489 | class ListPath { |
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| 490 | public: |
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| 491 | |
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[606] | 492 | typedef GR Digraph; |
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[96] | 493 | typedef typename Digraph::Arc Arc; |
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| 494 | |
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| 495 | protected: |
---|
| 496 | |
---|
[209] | 497 | // the std::list<> is incompatible |
---|
[96] | 498 | // hard to create invalid iterator |
---|
| 499 | struct Node { |
---|
| 500 | Arc arc; |
---|
| 501 | Node *next, *prev; |
---|
| 502 | }; |
---|
| 503 | |
---|
| 504 | Node *first, *last; |
---|
| 505 | |
---|
| 506 | std::allocator<Node> alloc; |
---|
| 507 | |
---|
| 508 | public: |
---|
[209] | 509 | |
---|
[96] | 510 | /// \brief Default constructor |
---|
| 511 | /// |
---|
| 512 | /// Default constructor |
---|
| 513 | ListPath() : first(0), last(0) {} |
---|
| 514 | |
---|
[1144] | 515 | /// \brief Copy constructor |
---|
| 516 | /// |
---|
| 517 | ListPath(const ListPath& cpath) : first(0), last(0) { |
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| 518 | pathCopy(cpath, *this); |
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| 519 | } |
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| 520 | |
---|
[96] | 521 | /// \brief Template copy constructor |
---|
| 522 | /// |
---|
| 523 | /// This path can be initialized with any other path type. It just |
---|
| 524 | /// makes a copy of the given path. |
---|
| 525 | template <typename CPath> |
---|
| 526 | ListPath(const CPath& cpath) : first(0), last(0) { |
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[551] | 527 | pathCopy(cpath, *this); |
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[96] | 528 | } |
---|
| 529 | |
---|
| 530 | /// \brief Destructor of the path |
---|
| 531 | /// |
---|
| 532 | /// Destructor of the path |
---|
| 533 | ~ListPath() { |
---|
| 534 | clear(); |
---|
| 535 | } |
---|
| 536 | |
---|
[1144] | 537 | /// \brief Copy assignment |
---|
| 538 | /// |
---|
| 539 | ListPath& operator=(const ListPath& cpath) { |
---|
| 540 | pathCopy(cpath, *this); |
---|
| 541 | return *this; |
---|
| 542 | } |
---|
| 543 | |
---|
[96] | 544 | /// \brief Template copy assignment |
---|
| 545 | /// |
---|
| 546 | /// This path can be initialized with any other path type. It just |
---|
| 547 | /// makes a copy of the given path. |
---|
| 548 | template <typename CPath> |
---|
| 549 | ListPath& operator=(const CPath& cpath) { |
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[551] | 550 | pathCopy(cpath, *this); |
---|
[96] | 551 | return *this; |
---|
| 552 | } |
---|
| 553 | |
---|
| 554 | /// \brief Iterator class to iterate on the arcs of the paths |
---|
| 555 | /// |
---|
| 556 | /// This class is used to iterate on the arcs of the paths |
---|
| 557 | /// |
---|
| 558 | /// Of course it converts to Digraph::Arc |
---|
| 559 | class ArcIt { |
---|
| 560 | friend class ListPath; |
---|
| 561 | public: |
---|
| 562 | /// Default constructor |
---|
| 563 | ArcIt() {} |
---|
| 564 | /// Invalid constructor |
---|
| 565 | ArcIt(Invalid) : path(0), node(0) {} |
---|
| 566 | /// \brief Initializate the constructor to the first arc of path |
---|
[209] | 567 | ArcIt(const ListPath &_path) |
---|
[96] | 568 | : path(&_path), node(_path.first) {} |
---|
| 569 | |
---|
| 570 | protected: |
---|
| 571 | |
---|
[209] | 572 | ArcIt(const ListPath &_path, Node *_node) |
---|
[96] | 573 | : path(&_path), node(_node) {} |
---|
| 574 | |
---|
| 575 | |
---|
| 576 | public: |
---|
| 577 | |
---|
| 578 | ///Conversion to Digraph::Arc |
---|
| 579 | operator const Arc&() const { |
---|
| 580 | return node->arc; |
---|
| 581 | } |
---|
| 582 | |
---|
| 583 | /// Next arc |
---|
[209] | 584 | ArcIt& operator++() { |
---|
[96] | 585 | node = node->next; |
---|
[209] | 586 | return *this; |
---|
[96] | 587 | } |
---|
| 588 | |
---|
| 589 | /// Comparison operator |
---|
| 590 | bool operator==(const ArcIt& e) const { return node==e.node; } |
---|
| 591 | /// Comparison operator |
---|
| 592 | bool operator!=(const ArcIt& e) const { return node!=e.node; } |
---|
| 593 | /// Comparison operator |
---|
| 594 | bool operator<(const ArcIt& e) const { return node<e.node; } |
---|
| 595 | |
---|
| 596 | private: |
---|
| 597 | const ListPath *path; |
---|
| 598 | Node *node; |
---|
| 599 | }; |
---|
| 600 | |
---|
[1336] | 601 | /// \brief Gets the collection of the arcs of the path. |
---|
| 602 | /// |
---|
| 603 | /// This function can be used for iterating on the |
---|
| 604 | /// arcs of the path. It returns a wrapped |
---|
| 605 | /// ArcIt, which looks like an STL container |
---|
| 606 | /// (by having begin() and end()) which you can use in range-based |
---|
| 607 | /// for loops, STL algorithms, etc. |
---|
| 608 | /// For example you can write: |
---|
| 609 | ///\code |
---|
| 610 | /// for(auto a: p.arcs()) |
---|
| 611 | /// doSomething(a); |
---|
| 612 | ///\endcode |
---|
| 613 | LemonRangeWrapper1<ArcIt, ListPath> arcs() const { |
---|
| 614 | return LemonRangeWrapper1<ArcIt, ListPath>(*this); |
---|
| 615 | } |
---|
| 616 | |
---|
| 617 | |
---|
[1024] | 618 | /// \brief The n-th arc. |
---|
[96] | 619 | /// |
---|
[1024] | 620 | /// This function looks for the n-th arc in O(n) time. |
---|
[1420] | 621 | /// \pre \c n is in the range <tt>[0..length() - 1]</tt>. |
---|
[96] | 622 | const Arc& nth(int n) const { |
---|
| 623 | Node *node = first; |
---|
| 624 | for (int i = 0; i < n; ++i) { |
---|
| 625 | node = node->next; |
---|
| 626 | } |
---|
| 627 | return node->arc; |
---|
| 628 | } |
---|
| 629 | |
---|
[1024] | 630 | /// \brief Initializes arc iterator to point to the n-th arc. |
---|
[96] | 631 | ArcIt nthIt(int n) const { |
---|
| 632 | Node *node = first; |
---|
| 633 | for (int i = 0; i < n; ++i) { |
---|
| 634 | node = node->next; |
---|
| 635 | } |
---|
| 636 | return ArcIt(*this, node); |
---|
| 637 | } |
---|
| 638 | |
---|
[1421] | 639 | /// \brief The n-th arc. |
---|
| 640 | /// |
---|
| 641 | /// Looks for the n-th arc in O(n) time. This operator is just an alias |
---|
| 642 | /// for \ref nth(). |
---|
| 643 | /// \pre \c n is in the range <tt>[0..length() - 1]</tt>. |
---|
| 644 | const Arc& operator[](int n) const { |
---|
| 645 | return nth(n); |
---|
| 646 | } |
---|
| 647 | |
---|
[96] | 648 | /// \brief Length of the path. |
---|
| 649 | int length() const { |
---|
| 650 | int len = 0; |
---|
| 651 | Node *node = first; |
---|
| 652 | while (node != 0) { |
---|
| 653 | node = node->next; |
---|
| 654 | ++len; |
---|
| 655 | } |
---|
| 656 | return len; |
---|
| 657 | } |
---|
| 658 | |
---|
[97] | 659 | /// \brief Return true if the path is empty. |
---|
[96] | 660 | bool empty() const { return first == 0; } |
---|
| 661 | |
---|
[97] | 662 | /// \brief Reset the path to an empty one. |
---|
[96] | 663 | void clear() { |
---|
| 664 | while (first != 0) { |
---|
| 665 | last = first->next; |
---|
| 666 | alloc.destroy(first); |
---|
| 667 | alloc.deallocate(first, 1); |
---|
| 668 | first = last; |
---|
| 669 | } |
---|
| 670 | } |
---|
| 671 | |
---|
[97] | 672 | /// \brief The first arc of the path |
---|
[96] | 673 | const Arc& front() const { |
---|
| 674 | return first->arc; |
---|
| 675 | } |
---|
| 676 | |
---|
| 677 | /// \brief Add a new arc before the current path |
---|
| 678 | void addFront(const Arc& arc) { |
---|
| 679 | Node *node = alloc.allocate(1); |
---|
| 680 | alloc.construct(node, Node()); |
---|
| 681 | node->prev = 0; |
---|
| 682 | node->next = first; |
---|
| 683 | node->arc = arc; |
---|
| 684 | if (first) { |
---|
| 685 | first->prev = node; |
---|
| 686 | first = node; |
---|
| 687 | } else { |
---|
| 688 | first = last = node; |
---|
| 689 | } |
---|
| 690 | } |
---|
| 691 | |
---|
| 692 | /// \brief Erase the first arc of the path |
---|
| 693 | void eraseFront() { |
---|
| 694 | Node *node = first; |
---|
| 695 | first = first->next; |
---|
| 696 | if (first) { |
---|
| 697 | first->prev = 0; |
---|
| 698 | } else { |
---|
| 699 | last = 0; |
---|
| 700 | } |
---|
| 701 | alloc.destroy(node); |
---|
| 702 | alloc.deallocate(node, 1); |
---|
| 703 | } |
---|
| 704 | |
---|
[97] | 705 | /// \brief The last arc of the path. |
---|
[96] | 706 | const Arc& back() const { |
---|
| 707 | return last->arc; |
---|
| 708 | } |
---|
| 709 | |
---|
| 710 | /// \brief Add a new arc behind the current path. |
---|
| 711 | void addBack(const Arc& arc) { |
---|
| 712 | Node *node = alloc.allocate(1); |
---|
| 713 | alloc.construct(node, Node()); |
---|
| 714 | node->next = 0; |
---|
| 715 | node->prev = last; |
---|
| 716 | node->arc = arc; |
---|
| 717 | if (last) { |
---|
| 718 | last->next = node; |
---|
| 719 | last = node; |
---|
| 720 | } else { |
---|
| 721 | last = first = node; |
---|
| 722 | } |
---|
| 723 | } |
---|
| 724 | |
---|
| 725 | /// \brief Erase the last arc of the path |
---|
| 726 | void eraseBack() { |
---|
| 727 | Node *node = last; |
---|
| 728 | last = last->prev; |
---|
| 729 | if (last) { |
---|
| 730 | last->next = 0; |
---|
| 731 | } else { |
---|
| 732 | first = 0; |
---|
| 733 | } |
---|
| 734 | alloc.destroy(node); |
---|
| 735 | alloc.deallocate(node, 1); |
---|
| 736 | } |
---|
| 737 | |
---|
[97] | 738 | /// \brief Splice a path to the back of the current path. |
---|
[96] | 739 | /// |
---|
[97] | 740 | /// It splices \c tpath to the back of the current path and \c |
---|
[96] | 741 | /// tpath becomes empty. The time complexity of this function is |
---|
| 742 | /// O(1). |
---|
| 743 | void spliceBack(ListPath& tpath) { |
---|
| 744 | if (first) { |
---|
| 745 | if (tpath.first) { |
---|
| 746 | last->next = tpath.first; |
---|
| 747 | tpath.first->prev = last; |
---|
| 748 | last = tpath.last; |
---|
| 749 | } |
---|
| 750 | } else { |
---|
| 751 | first = tpath.first; |
---|
| 752 | last = tpath.last; |
---|
| 753 | } |
---|
| 754 | tpath.first = tpath.last = 0; |
---|
| 755 | } |
---|
| 756 | |
---|
[97] | 757 | /// \brief Splice a path to the front of the current path. |
---|
[96] | 758 | /// |
---|
[97] | 759 | /// It splices \c tpath before the current path and \c tpath |
---|
[96] | 760 | /// becomes empty. The time complexity of this function |
---|
| 761 | /// is O(1). |
---|
| 762 | void spliceFront(ListPath& tpath) { |
---|
| 763 | if (first) { |
---|
| 764 | if (tpath.first) { |
---|
| 765 | first->prev = tpath.last; |
---|
| 766 | tpath.last->next = first; |
---|
| 767 | first = tpath.first; |
---|
| 768 | } |
---|
| 769 | } else { |
---|
| 770 | first = tpath.first; |
---|
| 771 | last = tpath.last; |
---|
| 772 | } |
---|
| 773 | tpath.first = tpath.last = 0; |
---|
| 774 | } |
---|
| 775 | |
---|
[97] | 776 | /// \brief Splice a path into the current path. |
---|
[96] | 777 | /// |
---|
| 778 | /// It splices the \c tpath into the current path before the |
---|
| 779 | /// position of \c it iterator and \c tpath becomes empty. The |
---|
[97] | 780 | /// time complexity of this function is O(1). If the \c it is |
---|
| 781 | /// \c INVALID then it will splice behind the current path. |
---|
[96] | 782 | void splice(ArcIt it, ListPath& tpath) { |
---|
| 783 | if (it.node) { |
---|
| 784 | if (tpath.first) { |
---|
| 785 | tpath.first->prev = it.node->prev; |
---|
| 786 | if (it.node->prev) { |
---|
| 787 | it.node->prev->next = tpath.first; |
---|
| 788 | } else { |
---|
| 789 | first = tpath.first; |
---|
| 790 | } |
---|
| 791 | it.node->prev = tpath.last; |
---|
| 792 | tpath.last->next = it.node; |
---|
| 793 | } |
---|
| 794 | } else { |
---|
| 795 | if (first) { |
---|
| 796 | if (tpath.first) { |
---|
| 797 | last->next = tpath.first; |
---|
| 798 | tpath.first->prev = last; |
---|
| 799 | last = tpath.last; |
---|
| 800 | } |
---|
| 801 | } else { |
---|
| 802 | first = tpath.first; |
---|
| 803 | last = tpath.last; |
---|
| 804 | } |
---|
| 805 | } |
---|
| 806 | tpath.first = tpath.last = 0; |
---|
| 807 | } |
---|
| 808 | |
---|
[97] | 809 | /// \brief Split the current path. |
---|
[96] | 810 | /// |
---|
[97] | 811 | /// It splits the current path into two parts. The part before |
---|
| 812 | /// the iterator \c it will remain in the current path and the part |
---|
| 813 | /// starting with |
---|
| 814 | /// \c it will put into \c tpath. If \c tpath have arcs |
---|
| 815 | /// before the operation they are removed first. The time |
---|
[1420] | 816 | /// complexity of this function is O(1) plus the time of emtying |
---|
[97] | 817 | /// \c tpath. If \c it is \c INVALID then it just clears \c tpath |
---|
[96] | 818 | void split(ArcIt it, ListPath& tpath) { |
---|
| 819 | tpath.clear(); |
---|
| 820 | if (it.node) { |
---|
| 821 | tpath.first = it.node; |
---|
| 822 | tpath.last = last; |
---|
| 823 | if (it.node->prev) { |
---|
| 824 | last = it.node->prev; |
---|
| 825 | last->next = 0; |
---|
| 826 | } else { |
---|
| 827 | first = last = 0; |
---|
| 828 | } |
---|
| 829 | it.node->prev = 0; |
---|
| 830 | } |
---|
| 831 | } |
---|
| 832 | |
---|
| 833 | |
---|
| 834 | typedef True BuildTag; |
---|
| 835 | |
---|
| 836 | template <typename CPath> |
---|
| 837 | void build(const CPath& path) { |
---|
| 838 | for (typename CPath::ArcIt it(path); it != INVALID; ++it) { |
---|
| 839 | addBack(it); |
---|
| 840 | } |
---|
| 841 | } |
---|
| 842 | |
---|
| 843 | template <typename CPath> |
---|
| 844 | void buildRev(const CPath& path) { |
---|
| 845 | for (typename CPath::RevArcIt it(path); it != INVALID; ++it) { |
---|
| 846 | addFront(it); |
---|
| 847 | } |
---|
| 848 | } |
---|
| 849 | |
---|
| 850 | }; |
---|
| 851 | |
---|
| 852 | /// \brief A structure for representing directed paths in a digraph. |
---|
| 853 | /// |
---|
| 854 | /// A structure for representing directed path in a digraph. |
---|
[606] | 855 | /// \tparam GR The digraph type in which the path is. |
---|
[96] | 856 | /// |
---|
[1420] | 857 | /// In a sense, a path can be treated as a list of arcs. The |
---|
| 858 | /// LEMON path type simply stores this list. As a consequence, it |
---|
| 859 | /// cannot enumerate the nodes in the path, and the source node of |
---|
| 860 | /// a zero-length path is undefined. |
---|
[96] | 861 | /// |
---|
[97] | 862 | /// This implementation is completly static, i.e. it can be copy constucted |
---|
| 863 | /// or copy assigned from another path, but otherwise it cannot be |
---|
| 864 | /// modified. |
---|
| 865 | /// |
---|
[1420] | 866 | /// Being the most memory-efficient path type in LEMON, it is |
---|
| 867 | /// intented to be used when you want to store a large number of paths. |
---|
[606] | 868 | template <typename GR> |
---|
[96] | 869 | class StaticPath { |
---|
| 870 | public: |
---|
| 871 | |
---|
[606] | 872 | typedef GR Digraph; |
---|
[96] | 873 | typedef typename Digraph::Arc Arc; |
---|
| 874 | |
---|
| 875 | /// \brief Default constructor |
---|
| 876 | /// |
---|
| 877 | /// Default constructor |
---|
[1336] | 878 | StaticPath() : len(0), _arcs(0) {} |
---|
[209] | 879 | |
---|
[1144] | 880 | /// \brief Copy constructor |
---|
| 881 | /// |
---|
[1336] | 882 | StaticPath(const StaticPath& cpath) : _arcs(0) { |
---|
[1144] | 883 | pathCopy(cpath, *this); |
---|
| 884 | } |
---|
| 885 | |
---|
[96] | 886 | /// \brief Template copy constructor |
---|
| 887 | /// |
---|
[97] | 888 | /// This path can be initialized from any other path type. |
---|
[96] | 889 | template <typename CPath> |
---|
[1336] | 890 | StaticPath(const CPath& cpath) : _arcs(0) { |
---|
[551] | 891 | pathCopy(cpath, *this); |
---|
[96] | 892 | } |
---|
| 893 | |
---|
| 894 | /// \brief Destructor of the path |
---|
| 895 | /// |
---|
| 896 | /// Destructor of the path |
---|
| 897 | ~StaticPath() { |
---|
[1336] | 898 | if (_arcs) delete[] _arcs; |
---|
[96] | 899 | } |
---|
| 900 | |
---|
[1144] | 901 | /// \brief Copy assignment |
---|
| 902 | /// |
---|
| 903 | StaticPath& operator=(const StaticPath& cpath) { |
---|
| 904 | pathCopy(cpath, *this); |
---|
| 905 | return *this; |
---|
| 906 | } |
---|
| 907 | |
---|
[96] | 908 | /// \brief Template copy assignment |
---|
| 909 | /// |
---|
[97] | 910 | /// This path can be made equal to any other path type. It simply |
---|
[96] | 911 | /// makes a copy of the given path. |
---|
| 912 | template <typename CPath> |
---|
| 913 | StaticPath& operator=(const CPath& cpath) { |
---|
[551] | 914 | pathCopy(cpath, *this); |
---|
[96] | 915 | return *this; |
---|
| 916 | } |
---|
| 917 | |
---|
| 918 | /// \brief Iterator class to iterate on the arcs of the paths |
---|
| 919 | /// |
---|
| 920 | /// This class is used to iterate on the arcs of the paths |
---|
| 921 | /// |
---|
| 922 | /// Of course it converts to Digraph::Arc |
---|
| 923 | class ArcIt { |
---|
| 924 | friend class StaticPath; |
---|
| 925 | public: |
---|
| 926 | /// Default constructor |
---|
| 927 | ArcIt() {} |
---|
| 928 | /// Invalid constructor |
---|
| 929 | ArcIt(Invalid) : path(0), idx(-1) {} |
---|
| 930 | /// Initializate the constructor to the first arc of path |
---|
[209] | 931 | ArcIt(const StaticPath &_path) |
---|
[96] | 932 | : path(&_path), idx(_path.empty() ? -1 : 0) {} |
---|
| 933 | |
---|
| 934 | private: |
---|
| 935 | |
---|
| 936 | /// Constructor with starting point |
---|
[209] | 937 | ArcIt(const StaticPath &_path, int _idx) |
---|
[96] | 938 | : idx(_idx), path(&_path) {} |
---|
| 939 | |
---|
| 940 | public: |
---|
| 941 | |
---|
| 942 | ///Conversion to Digraph::Arc |
---|
| 943 | operator const Arc&() const { |
---|
| 944 | return path->nth(idx); |
---|
| 945 | } |
---|
| 946 | |
---|
| 947 | /// Next arc |
---|
[209] | 948 | ArcIt& operator++() { |
---|
[96] | 949 | ++idx; |
---|
[209] | 950 | if (idx >= path->length()) idx = -1; |
---|
| 951 | return *this; |
---|
[96] | 952 | } |
---|
| 953 | |
---|
| 954 | /// Comparison operator |
---|
| 955 | bool operator==(const ArcIt& e) const { return idx==e.idx; } |
---|
| 956 | /// Comparison operator |
---|
| 957 | bool operator!=(const ArcIt& e) const { return idx!=e.idx; } |
---|
| 958 | /// Comparison operator |
---|
| 959 | bool operator<(const ArcIt& e) const { return idx<e.idx; } |
---|
| 960 | |
---|
| 961 | private: |
---|
| 962 | const StaticPath *path; |
---|
| 963 | int idx; |
---|
| 964 | }; |
---|
[1336] | 965 | |
---|
| 966 | /// \brief Gets the collection of the arcs of the path. |
---|
| 967 | /// |
---|
| 968 | /// This function can be used for iterating on the |
---|
| 969 | /// arcs of the path. It returns a wrapped |
---|
| 970 | /// ArcIt, which looks like an STL container |
---|
| 971 | /// (by having begin() and end()) which you can use in range-based |
---|
| 972 | /// for loops, STL algorithms, etc. |
---|
| 973 | /// For example you can write: |
---|
| 974 | ///\code |
---|
| 975 | /// for(auto a: p.arcs()) |
---|
| 976 | /// doSomething(a); |
---|
| 977 | ///\endcode |
---|
| 978 | LemonRangeWrapper1<ArcIt, StaticPath> arcs() const { |
---|
| 979 | return LemonRangeWrapper1<ArcIt, StaticPath>(*this); |
---|
| 980 | } |
---|
| 981 | |
---|
[96] | 982 | |
---|
[1024] | 983 | /// \brief The n-th arc. |
---|
[96] | 984 | /// |
---|
[1420] | 985 | /// Gives back the n-th arc. This function runs in O(1) time. |
---|
| 986 | /// \pre \c n is in the range <tt>[0..length() - 1]</tt>. |
---|
[96] | 987 | const Arc& nth(int n) const { |
---|
[1336] | 988 | return _arcs[n]; |
---|
[96] | 989 | } |
---|
| 990 | |
---|
[1024] | 991 | /// \brief The arc iterator pointing to the n-th arc. |
---|
[96] | 992 | ArcIt nthIt(int n) const { |
---|
| 993 | return ArcIt(*this, n); |
---|
| 994 | } |
---|
| 995 | |
---|
[1421] | 996 | /// \brief The n-th arc. |
---|
| 997 | /// |
---|
| 998 | /// Gives back the n-th arc. This operator is just an alias for \ref nth(), |
---|
| 999 | /// it runs in O(1) time. |
---|
| 1000 | /// \pre \c n is in the range <tt>[0..length() - 1]</tt>. |
---|
| 1001 | const Arc& operator[](int n) const { |
---|
| 1002 | return _arcs[n]; |
---|
| 1003 | } |
---|
| 1004 | |
---|
[97] | 1005 | /// \brief The length of the path. |
---|
[96] | 1006 | int length() const { return len; } |
---|
| 1007 | |
---|
[97] | 1008 | /// \brief Return true when the path is empty. |
---|
[96] | 1009 | int empty() const { return len == 0; } |
---|
| 1010 | |
---|
[1420] | 1011 | /// \brief Reset the path to an empty one. |
---|
[96] | 1012 | void clear() { |
---|
| 1013 | len = 0; |
---|
[1336] | 1014 | if (_arcs) delete[] _arcs; |
---|
| 1015 | _arcs = 0; |
---|
[96] | 1016 | } |
---|
| 1017 | |
---|
[97] | 1018 | /// \brief The first arc of the path. |
---|
[96] | 1019 | const Arc& front() const { |
---|
[1336] | 1020 | return _arcs[0]; |
---|
[96] | 1021 | } |
---|
| 1022 | |
---|
[97] | 1023 | /// \brief The last arc of the path. |
---|
[96] | 1024 | const Arc& back() const { |
---|
[1336] | 1025 | return _arcs[len - 1]; |
---|
[96] | 1026 | } |
---|
| 1027 | |
---|
| 1028 | |
---|
| 1029 | typedef True BuildTag; |
---|
| 1030 | |
---|
| 1031 | template <typename CPath> |
---|
| 1032 | void build(const CPath& path) { |
---|
| 1033 | len = path.length(); |
---|
[1336] | 1034 | _arcs = new Arc[len]; |
---|
[96] | 1035 | int index = 0; |
---|
| 1036 | for (typename CPath::ArcIt it(path); it != INVALID; ++it) { |
---|
[1336] | 1037 | _arcs[index] = it; |
---|
[96] | 1038 | ++index; |
---|
| 1039 | } |
---|
| 1040 | } |
---|
| 1041 | |
---|
| 1042 | template <typename CPath> |
---|
| 1043 | void buildRev(const CPath& path) { |
---|
| 1044 | len = path.length(); |
---|
[1336] | 1045 | _arcs = new Arc[len]; |
---|
[96] | 1046 | int index = len; |
---|
| 1047 | for (typename CPath::RevArcIt it(path); it != INVALID; ++it) { |
---|
| 1048 | --index; |
---|
[1336] | 1049 | _arcs[index] = it; |
---|
[96] | 1050 | } |
---|
| 1051 | } |
---|
| 1052 | |
---|
| 1053 | private: |
---|
| 1054 | int len; |
---|
[1336] | 1055 | Arc* _arcs; |
---|
[96] | 1056 | }; |
---|
| 1057 | |
---|
[98] | 1058 | /////////////////////////////////////////////////////////////////////// |
---|
| 1059 | // Additional utilities |
---|
| 1060 | /////////////////////////////////////////////////////////////////////// |
---|
| 1061 | |
---|
| 1062 | namespace _path_bits { |
---|
| 1063 | |
---|
| 1064 | template <typename Path, typename Enable = void> |
---|
[144] | 1065 | struct RevPathTagIndicator { |
---|
[98] | 1066 | static const bool value = false; |
---|
| 1067 | }; |
---|
| 1068 | |
---|
[144] | 1069 | template <typename Path> |
---|
| 1070 | struct RevPathTagIndicator< |
---|
[209] | 1071 | Path, |
---|
[144] | 1072 | typename enable_if<typename Path::RevPathTag, void>::type |
---|
| 1073 | > { |
---|
| 1074 | static const bool value = true; |
---|
| 1075 | }; |
---|
| 1076 | |
---|
| 1077 | template <typename Path, typename Enable = void> |
---|
| 1078 | struct BuildTagIndicator { |
---|
| 1079 | static const bool value = false; |
---|
| 1080 | }; |
---|
| 1081 | |
---|
| 1082 | template <typename Path> |
---|
| 1083 | struct BuildTagIndicator< |
---|
[209] | 1084 | Path, |
---|
[144] | 1085 | typename enable_if<typename Path::BuildTag, void>::type |
---|
[98] | 1086 | > { |
---|
| 1087 | static const bool value = true; |
---|
| 1088 | }; |
---|
| 1089 | |
---|
[551] | 1090 | template <typename From, typename To, |
---|
| 1091 | bool buildEnable = BuildTagIndicator<To>::value> |
---|
[517] | 1092 | struct PathCopySelectorForward { |
---|
[551] | 1093 | static void copy(const From& from, To& to) { |
---|
| 1094 | to.clear(); |
---|
| 1095 | for (typename From::ArcIt it(from); it != INVALID; ++it) { |
---|
| 1096 | to.addBack(it); |
---|
[98] | 1097 | } |
---|
| 1098 | } |
---|
| 1099 | }; |
---|
| 1100 | |
---|
[551] | 1101 | template <typename From, typename To> |
---|
| 1102 | struct PathCopySelectorForward<From, To, true> { |
---|
| 1103 | static void copy(const From& from, To& to) { |
---|
| 1104 | to.clear(); |
---|
| 1105 | to.build(from); |
---|
[517] | 1106 | } |
---|
| 1107 | }; |
---|
| 1108 | |
---|
[551] | 1109 | template <typename From, typename To, |
---|
| 1110 | bool buildEnable = BuildTagIndicator<To>::value> |
---|
[517] | 1111 | struct PathCopySelectorBackward { |
---|
[551] | 1112 | static void copy(const From& from, To& to) { |
---|
| 1113 | to.clear(); |
---|
| 1114 | for (typename From::RevArcIt it(from); it != INVALID; ++it) { |
---|
| 1115 | to.addFront(it); |
---|
[98] | 1116 | } |
---|
| 1117 | } |
---|
| 1118 | }; |
---|
| 1119 | |
---|
[551] | 1120 | template <typename From, typename To> |
---|
| 1121 | struct PathCopySelectorBackward<From, To, true> { |
---|
| 1122 | static void copy(const From& from, To& to) { |
---|
| 1123 | to.clear(); |
---|
| 1124 | to.buildRev(from); |
---|
[98] | 1125 | } |
---|
| 1126 | }; |
---|
| 1127 | |
---|
[956] | 1128 | |
---|
[551] | 1129 | template <typename From, typename To, |
---|
| 1130 | bool revEnable = RevPathTagIndicator<From>::value> |
---|
[517] | 1131 | struct PathCopySelector { |
---|
[551] | 1132 | static void copy(const From& from, To& to) { |
---|
| 1133 | PathCopySelectorForward<From, To>::copy(from, to); |
---|
[956] | 1134 | } |
---|
[517] | 1135 | }; |
---|
| 1136 | |
---|
[551] | 1137 | template <typename From, typename To> |
---|
| 1138 | struct PathCopySelector<From, To, true> { |
---|
| 1139 | static void copy(const From& from, To& to) { |
---|
| 1140 | PathCopySelectorBackward<From, To>::copy(from, to); |
---|
[956] | 1141 | } |
---|
[517] | 1142 | }; |
---|
| 1143 | |
---|
[98] | 1144 | } |
---|
| 1145 | |
---|
| 1146 | |
---|
| 1147 | /// \brief Make a copy of a path. |
---|
| 1148 | /// |
---|
[551] | 1149 | /// This function makes a copy of a path. |
---|
| 1150 | template <typename From, typename To> |
---|
| 1151 | void pathCopy(const From& from, To& to) { |
---|
| 1152 | checkConcept<concepts::PathDumper<typename From::Digraph>, From>(); |
---|
| 1153 | _path_bits::PathCopySelector<From, To>::copy(from, to); |
---|
| 1154 | } |
---|
| 1155 | |
---|
| 1156 | /// \brief Deprecated version of \ref pathCopy(). |
---|
| 1157 | /// |
---|
| 1158 | /// Deprecated version of \ref pathCopy() (only for reverse compatibility). |
---|
| 1159 | template <typename To, typename From> |
---|
| 1160 | void copyPath(To& to, const From& from) { |
---|
| 1161 | pathCopy(from, to); |
---|
[98] | 1162 | } |
---|
| 1163 | |
---|
| 1164 | /// \brief Check the consistency of a path. |
---|
| 1165 | /// |
---|
| 1166 | /// This function checks that the target of each arc is the same |
---|
[209] | 1167 | /// as the source of the next one. |
---|
| 1168 | /// |
---|
[98] | 1169 | template <typename Digraph, typename Path> |
---|
| 1170 | bool checkPath(const Digraph& digraph, const Path& path) { |
---|
| 1171 | typename Path::ArcIt it(path); |
---|
| 1172 | if (it == INVALID) return true; |
---|
| 1173 | typename Digraph::Node node = digraph.target(it); |
---|
| 1174 | ++it; |
---|
| 1175 | while (it != INVALID) { |
---|
| 1176 | if (digraph.source(it) != node) return false; |
---|
| 1177 | node = digraph.target(it); |
---|
| 1178 | ++it; |
---|
| 1179 | } |
---|
| 1180 | return true; |
---|
| 1181 | } |
---|
| 1182 | |
---|
| 1183 | /// \brief The source of a path |
---|
| 1184 | /// |
---|
[548] | 1185 | /// This function returns the source node of the given path. |
---|
| 1186 | /// If the path is empty, then it returns \c INVALID. |
---|
[98] | 1187 | template <typename Digraph, typename Path> |
---|
| 1188 | typename Digraph::Node pathSource(const Digraph& digraph, const Path& path) { |
---|
[548] | 1189 | return path.empty() ? INVALID : digraph.source(path.front()); |
---|
[98] | 1190 | } |
---|
| 1191 | |
---|
| 1192 | /// \brief The target of a path |
---|
| 1193 | /// |
---|
[548] | 1194 | /// This function returns the target node of the given path. |
---|
| 1195 | /// If the path is empty, then it returns \c INVALID. |
---|
[98] | 1196 | template <typename Digraph, typename Path> |
---|
| 1197 | typename Digraph::Node pathTarget(const Digraph& digraph, const Path& path) { |
---|
[548] | 1198 | return path.empty() ? INVALID : digraph.target(path.back()); |
---|
[98] | 1199 | } |
---|
| 1200 | |
---|
[1420] | 1201 | /// \brief Class for iterating through the nodes of a path |
---|
[98] | 1202 | /// |
---|
[1420] | 1203 | /// Class for iterating through the nodes of a path. |
---|
[98] | 1204 | /// |
---|
[1420] | 1205 | /// In a sense, a path can be treated as a list of arcs. The |
---|
| 1206 | /// LEMON path type simply stores this list. As a consequence, it |
---|
| 1207 | /// cannot enumerate the nodes in the path, and the source node of |
---|
| 1208 | /// a zero-length path is undefined. |
---|
| 1209 | /// |
---|
| 1210 | /// However, this class implements a node iterator for path structures. |
---|
| 1211 | /// To provide this feature, the underlying digraph should be passed to |
---|
[98] | 1212 | /// the constructor of the iterator. |
---|
| 1213 | template <typename Path> |
---|
| 1214 | class PathNodeIt { |
---|
| 1215 | private: |
---|
| 1216 | const typename Path::Digraph *_digraph; |
---|
| 1217 | typename Path::ArcIt _it; |
---|
| 1218 | typename Path::Digraph::Node _nd; |
---|
| 1219 | |
---|
| 1220 | public: |
---|
| 1221 | |
---|
| 1222 | typedef typename Path::Digraph Digraph; |
---|
| 1223 | typedef typename Digraph::Node Node; |
---|
[209] | 1224 | |
---|
[98] | 1225 | /// Default constructor |
---|
| 1226 | PathNodeIt() {} |
---|
| 1227 | /// Invalid constructor |
---|
[209] | 1228 | PathNodeIt(Invalid) |
---|
[98] | 1229 | : _digraph(0), _it(INVALID), _nd(INVALID) {} |
---|
| 1230 | /// Constructor |
---|
[209] | 1231 | PathNodeIt(const Digraph& digraph, const Path& path) |
---|
[98] | 1232 | : _digraph(&digraph), _it(path) { |
---|
| 1233 | _nd = (_it != INVALID ? _digraph->source(_it) : INVALID); |
---|
| 1234 | } |
---|
| 1235 | /// Constructor |
---|
[209] | 1236 | PathNodeIt(const Digraph& digraph, const Path& path, const Node& src) |
---|
[98] | 1237 | : _digraph(&digraph), _it(path), _nd(src) {} |
---|
| 1238 | |
---|
| 1239 | ///Conversion to Digraph::Node |
---|
| 1240 | operator Node() const { |
---|
| 1241 | return _nd; |
---|
| 1242 | } |
---|
| 1243 | |
---|
| 1244 | /// Next node |
---|
| 1245 | PathNodeIt& operator++() { |
---|
| 1246 | if (_it == INVALID) _nd = INVALID; |
---|
| 1247 | else { |
---|
[209] | 1248 | _nd = _digraph->target(_it); |
---|
| 1249 | ++_it; |
---|
[98] | 1250 | } |
---|
| 1251 | return *this; |
---|
| 1252 | } |
---|
| 1253 | |
---|
| 1254 | /// Comparison operator |
---|
[209] | 1255 | bool operator==(const PathNodeIt& n) const { |
---|
| 1256 | return _it == n._it && _nd == n._nd; |
---|
[98] | 1257 | } |
---|
| 1258 | /// Comparison operator |
---|
[209] | 1259 | bool operator!=(const PathNodeIt& n) const { |
---|
| 1260 | return _it != n._it || _nd != n._nd; |
---|
[98] | 1261 | } |
---|
| 1262 | /// Comparison operator |
---|
[209] | 1263 | bool operator<(const PathNodeIt& n) const { |
---|
[98] | 1264 | return (_it < n._it && _nd != INVALID); |
---|
| 1265 | } |
---|
[209] | 1266 | |
---|
[98] | 1267 | }; |
---|
[209] | 1268 | |
---|
[1336] | 1269 | /// \brief Gets the collection of the nodes of the path. |
---|
| 1270 | /// |
---|
| 1271 | /// This function can be used for iterating on the |
---|
| 1272 | /// nodes of the path. It returns a wrapped |
---|
| 1273 | /// PathNodeIt, which looks like an STL container |
---|
| 1274 | /// (by having begin() and end()) which you can use in range-based |
---|
| 1275 | /// for loops, STL algorithms, etc. |
---|
| 1276 | /// For example you can write: |
---|
| 1277 | ///\code |
---|
| 1278 | /// for(auto u: pathNodes(g,p)) |
---|
| 1279 | /// doSomething(u); |
---|
| 1280 | ///\endcode |
---|
| 1281 | template<typename Path> |
---|
| 1282 | LemonRangeWrapper2<PathNodeIt<Path>, typename Path::Digraph, Path> |
---|
| 1283 | pathNodes(const typename Path::Digraph &g, const Path &p) { |
---|
| 1284 | return |
---|
| 1285 | LemonRangeWrapper2<PathNodeIt<Path>, typename Path::Digraph, Path>(g,p); |
---|
| 1286 | } |
---|
| 1287 | |
---|
[96] | 1288 | ///@} |
---|
| 1289 | |
---|
| 1290 | } // namespace lemon |
---|
| 1291 | |
---|
| 1292 | #endif // LEMON_PATH_H |
---|