[109] | 1 | /* -*- C++ -*- |
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| 2 | * |
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| 3 | * This file is a part of LEMON, a generic C++ optimization library |
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| 4 | * |
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| 5 | * Copyright (C) 2003-2008 |
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| 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 | #ifndef LEMON_SMART_GRAPH_H |
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| 20 | #define LEMON_SMART_GRAPH_H |
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| 21 | |
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| 22 | ///\ingroup graphs |
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| 23 | ///\file |
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| 24 | ///\brief SmartDigraph and SmartGraph classes. |
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| 25 | |
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| 26 | #include <vector> |
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| 27 | |
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| 28 | #include <lemon/bits/invalid.h> |
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| 29 | |
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| 30 | #include <lemon/bits/base_extender.h> |
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| 31 | #include <lemon/bits/graph_extender.h> |
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| 32 | |
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| 33 | #include <lemon/bits/utility.h> |
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| 34 | #include <lemon/error.h> |
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| 35 | |
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| 36 | #include <lemon/bits/graph_extender.h> |
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| 37 | |
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| 38 | namespace lemon { |
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| 39 | |
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| 40 | class SmartDigraph; |
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| 41 | ///Base of SmartDigraph |
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| 42 | |
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| 43 | ///Base of SmartDigraph |
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| 44 | /// |
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| 45 | class SmartDigraphBase { |
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| 46 | protected: |
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| 47 | |
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| 48 | struct NodeT |
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| 49 | { |
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| 50 | int first_in, first_out; |
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| 51 | NodeT() {} |
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| 52 | }; |
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| 53 | struct ArcT |
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| 54 | { |
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| 55 | int target, source, next_in, next_out; |
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| 56 | ArcT() {} |
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| 57 | }; |
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| 58 | |
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| 59 | std::vector<NodeT> nodes; |
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| 60 | std::vector<ArcT> arcs; |
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| 61 | |
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| 62 | public: |
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| 63 | |
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| 64 | typedef SmartDigraphBase Graph; |
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| 65 | |
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| 66 | class Node; |
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| 67 | class Arc; |
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| 68 | |
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| 69 | public: |
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| 70 | |
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| 71 | SmartDigraphBase() : nodes(), arcs() { } |
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| 72 | SmartDigraphBase(const SmartDigraphBase &_g) |
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| 73 | : nodes(_g.nodes), arcs(_g.arcs) { } |
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| 74 | |
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| 75 | typedef True NodeNumTag; |
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| 76 | typedef True ArcNumTag; |
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| 77 | |
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| 78 | int nodeNum() const { return nodes.size(); } |
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| 79 | int arcNum() const { return arcs.size(); } |
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| 80 | |
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| 81 | int maxNodeId() const { return nodes.size()-1; } |
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| 82 | int maxArcId() const { return arcs.size()-1; } |
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| 83 | |
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| 84 | Node addNode() { |
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| 85 | int n = nodes.size(); |
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| 86 | nodes.push_back(NodeT()); |
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| 87 | nodes[n].first_in = -1; |
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| 88 | nodes[n].first_out = -1; |
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| 89 | return Node(n); |
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| 90 | } |
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| 91 | |
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| 92 | Arc addArc(Node u, Node v) { |
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| 93 | int n = arcs.size(); |
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| 94 | arcs.push_back(ArcT()); |
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| 95 | arcs[n].source = u._id; |
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| 96 | arcs[n].target = v._id; |
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| 97 | arcs[n].next_out = nodes[u._id].first_out; |
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| 98 | arcs[n].next_in = nodes[v._id].first_in; |
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| 99 | nodes[u._id].first_out = nodes[v._id].first_in = n; |
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| 100 | |
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| 101 | return Arc(n); |
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| 102 | } |
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| 103 | |
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| 104 | void clear() { |
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| 105 | arcs.clear(); |
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| 106 | nodes.clear(); |
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| 107 | } |
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| 108 | |
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| 109 | Node source(Arc a) const { return Node(arcs[a._id].source); } |
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| 110 | Node target(Arc a) const { return Node(arcs[a._id].target); } |
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| 111 | |
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| 112 | static int id(Node v) { return v._id; } |
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| 113 | static int id(Arc a) { return a._id; } |
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| 114 | |
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| 115 | static Node nodeFromId(int id) { return Node(id);} |
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| 116 | static Arc arcFromId(int id) { return Arc(id);} |
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| 117 | |
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| 118 | class Node { |
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| 119 | friend class SmartDigraphBase; |
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| 120 | friend class SmartDigraph; |
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| 121 | |
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| 122 | protected: |
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| 123 | int _id; |
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| 124 | explicit Node(int id) : _id(id) {} |
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| 125 | public: |
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| 126 | Node() {} |
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| 127 | Node (Invalid) : _id(-1) {} |
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| 128 | bool operator==(const Node i) const {return _id == i._id;} |
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| 129 | bool operator!=(const Node i) const {return _id != i._id;} |
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| 130 | bool operator<(const Node i) const {return _id < i._id;} |
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| 131 | }; |
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| 132 | |
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| 133 | |
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| 134 | class Arc { |
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| 135 | friend class SmartDigraphBase; |
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| 136 | friend class SmartDigraph; |
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| 137 | |
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| 138 | protected: |
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| 139 | int _id; |
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| 140 | explicit Arc(int id) : _id(id) {} |
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| 141 | public: |
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| 142 | Arc() { } |
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| 143 | Arc (Invalid) : _id(-1) {} |
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| 144 | bool operator==(const Arc i) const {return _id == i._id;} |
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| 145 | bool operator!=(const Arc i) const {return _id != i._id;} |
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| 146 | bool operator<(const Arc i) const {return _id < i._id;} |
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| 147 | }; |
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| 148 | |
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| 149 | void first(Node& node) const { |
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| 150 | node._id = nodes.size() - 1; |
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| 151 | } |
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| 152 | |
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| 153 | static void next(Node& node) { |
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| 154 | --node._id; |
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| 155 | } |
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| 156 | |
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| 157 | void first(Arc& arc) const { |
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| 158 | arc._id = arcs.size() - 1; |
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| 159 | } |
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| 160 | |
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| 161 | static void next(Arc& arc) { |
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| 162 | --arc._id; |
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| 163 | } |
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| 164 | |
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| 165 | void firstOut(Arc& arc, const Node& node) const { |
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| 166 | arc._id = nodes[node._id].first_out; |
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| 167 | } |
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| 168 | |
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| 169 | void nextOut(Arc& arc) const { |
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| 170 | arc._id = arcs[arc._id].next_out; |
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| 171 | } |
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| 172 | |
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| 173 | void firstIn(Arc& arc, const Node& node) const { |
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| 174 | arc._id = nodes[node._id].first_in; |
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| 175 | } |
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| 176 | |
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| 177 | void nextIn(Arc& arc) const { |
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| 178 | arc._id = arcs[arc._id].next_in; |
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| 179 | } |
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| 180 | |
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| 181 | }; |
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| 182 | |
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| 183 | typedef DigraphExtender<SmartDigraphBase> ExtendedSmartDigraphBase; |
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| 184 | |
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| 185 | ///\ingroup graphs |
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| 186 | /// |
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| 187 | ///\brief A smart directed graph class. |
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| 188 | /// |
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| 189 | ///This is a simple and fast digraph implementation. |
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| 190 | ///It is also quite memory efficient, but at the price |
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| 191 | ///that <b> it does support only limited (only stack-like) |
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| 192 | ///node and arc deletions</b>. |
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| 193 | ///It conforms to the \ref concepts::Digraph "Digraph concept" with |
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| 194 | ///an important extra feature that its maps are real \ref |
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| 195 | ///concepts::ReferenceMap "reference map"s. |
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| 196 | /// |
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| 197 | ///\sa concepts::Digraph. |
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| 198 | /// |
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| 199 | ///\author Alpar Juttner |
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| 200 | class SmartDigraph : public ExtendedSmartDigraphBase { |
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| 201 | public: |
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| 202 | |
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| 203 | typedef ExtendedSmartDigraphBase Parent; |
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| 204 | |
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| 205 | private: |
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| 206 | |
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| 207 | ///SmartDigraph is \e not copy constructible. Use DigraphCopy() instead. |
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| 208 | |
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| 209 | ///SmartDigraph is \e not copy constructible. Use DigraphCopy() instead. |
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| 210 | /// |
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| 211 | SmartDigraph(const SmartDigraph &) : ExtendedSmartDigraphBase() {}; |
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| 212 | ///\brief Assignment of SmartDigraph to another one is \e not allowed. |
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| 213 | ///Use DigraphCopy() instead. |
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| 214 | |
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| 215 | ///Assignment of SmartDigraph to another one is \e not allowed. |
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| 216 | ///Use DigraphCopy() instead. |
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| 217 | void operator=(const SmartDigraph &) {} |
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| 218 | |
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| 219 | public: |
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| 220 | |
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| 221 | /// Constructor |
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| 222 | |
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| 223 | /// Constructor. |
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| 224 | /// |
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| 225 | SmartDigraph() {}; |
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| 226 | |
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| 227 | ///Add a new node to the digraph. |
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| 228 | |
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| 229 | /// \return the new node. |
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| 230 | /// |
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| 231 | Node addNode() { return Parent::addNode(); } |
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| 232 | |
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| 233 | ///Add a new arc to the digraph. |
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| 234 | |
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| 235 | ///Add a new arc to the digraph with source node \c s |
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| 236 | ///and target node \c t. |
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| 237 | ///\return the new arc. |
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| 238 | Arc addArc(const Node& s, const Node& t) { |
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| 239 | return Parent::addArc(s, t); |
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| 240 | } |
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| 241 | |
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| 242 | /// \brief Using this it is possible to avoid the superfluous memory |
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| 243 | /// allocation. |
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| 244 | |
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| 245 | /// Using this it is possible to avoid the superfluous memory |
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| 246 | /// allocation: if you know that the digraph you want to build will |
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| 247 | /// be very large (e.g. it will contain millions of nodes and/or arcs) |
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| 248 | /// then it is worth reserving space for this amount before starting |
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| 249 | /// to build the digraph. |
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| 250 | /// \sa reserveArc |
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| 251 | void reserveNode(int n) { nodes.reserve(n); }; |
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| 252 | |
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| 253 | /// \brief Using this it is possible to avoid the superfluous memory |
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| 254 | /// allocation. |
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| 255 | |
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| 256 | /// Using this it is possible to avoid the superfluous memory |
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| 257 | /// allocation: if you know that the digraph you want to build will |
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| 258 | /// be very large (e.g. it will contain millions of nodes and/or arcs) |
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| 259 | /// then it is worth reserving space for this amount before starting |
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| 260 | /// to build the digraph. |
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| 261 | /// \sa reserveNode |
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| 262 | void reserveArc(int m) { arcs.reserve(m); }; |
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| 263 | |
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| 264 | ///Clear the digraph. |
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| 265 | |
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| 266 | ///Erase all the nodes and arcs from the digraph. |
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| 267 | /// |
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| 268 | void clear() { |
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| 269 | Parent::clear(); |
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| 270 | } |
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| 271 | |
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| 272 | ///Split a node. |
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| 273 | |
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| 274 | ///This function splits a node. First a new node is added to the digraph, |
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| 275 | ///then the source of each outgoing arc of \c n is moved to this new node. |
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| 276 | ///If \c connect is \c true (this is the default value), then a new arc |
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| 277 | ///from \c n to the newly created node is also added. |
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| 278 | ///\return The newly created node. |
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| 279 | /// |
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| 280 | ///\note The <tt>Arc</tt>s |
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| 281 | ///referencing a moved arc remain |
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| 282 | ///valid. However <tt>InArc</tt>'s and <tt>OutArc</tt>'s |
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| 283 | ///may be invalidated. |
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| 284 | ///\warning This functionality cannot be used together with the Snapshot |
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| 285 | ///feature. |
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| 286 | ///\todo It could be implemented in a bit faster way. |
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| 287 | Node split(Node n, bool connect = true) |
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| 288 | { |
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| 289 | Node b = addNode(); |
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| 290 | nodes[b._id].first_out=nodes[n._id].first_out; |
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| 291 | nodes[n._id].first_out=-1; |
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| 292 | for(int i=nodes[b._id].first_out;i!=-1;i++) arcs[i].source=b._id; |
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| 293 | if(connect) addArc(n,b); |
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| 294 | return b; |
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| 295 | } |
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| 296 | |
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| 297 | public: |
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| 298 | |
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| 299 | class Snapshot; |
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| 300 | |
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| 301 | protected: |
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| 302 | |
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| 303 | void restoreSnapshot(const Snapshot &s) |
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| 304 | { |
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| 305 | while(s.arc_num<arcs.size()) { |
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| 306 | Arc arc = arcFromId(arcs.size()-1); |
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| 307 | Parent::notifier(Arc()).erase(arc); |
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| 308 | nodes[arcs.back().source].first_out=arcs.back().next_out; |
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| 309 | nodes[arcs.back().target].first_in=arcs.back().next_in; |
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| 310 | arcs.pop_back(); |
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| 311 | } |
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| 312 | while(s.node_num<nodes.size()) { |
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| 313 | Node node = nodeFromId(nodes.size()-1); |
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| 314 | Parent::notifier(Node()).erase(node); |
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| 315 | nodes.pop_back(); |
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| 316 | } |
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| 317 | } |
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| 318 | |
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| 319 | public: |
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| 320 | |
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| 321 | ///Class to make a snapshot of the digraph and to restrore to it later. |
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| 322 | |
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| 323 | ///Class to make a snapshot of the digraph and to restrore to it later. |
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| 324 | /// |
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| 325 | ///The newly added nodes and arcs can be removed using the |
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| 326 | ///restore() function. |
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| 327 | ///\note After you restore a state, you cannot restore |
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| 328 | ///a later state, in other word you cannot add again the arcs deleted |
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| 329 | ///by restore() using another one Snapshot instance. |
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| 330 | /// |
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| 331 | ///\warning If you do not use correctly the snapshot that can cause |
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| 332 | ///either broken program, invalid state of the digraph, valid but |
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| 333 | ///not the restored digraph or no change. Because the runtime performance |
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| 334 | ///the validity of the snapshot is not stored. |
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| 335 | class Snapshot |
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| 336 | { |
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| 337 | SmartDigraph *_graph; |
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| 338 | protected: |
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| 339 | friend class SmartDigraph; |
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| 340 | unsigned int node_num; |
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| 341 | unsigned int arc_num; |
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| 342 | public: |
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| 343 | ///Default constructor. |
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| 344 | |
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| 345 | ///Default constructor. |
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| 346 | ///To actually make a snapshot you must call save(). |
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| 347 | /// |
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| 348 | Snapshot() : _graph(0) {} |
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| 349 | ///Constructor that immediately makes a snapshot |
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| 350 | |
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| 351 | ///This constructor immediately makes a snapshot of the digraph. |
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| 352 | ///\param _g The digraph we make a snapshot of. |
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| 353 | Snapshot(SmartDigraph &graph) : _graph(&graph) { |
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| 354 | node_num=_graph->nodes.size(); |
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| 355 | arc_num=_graph->arcs.size(); |
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| 356 | } |
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| 357 | |
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| 358 | ///Make a snapshot. |
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| 359 | |
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| 360 | ///Make a snapshot of the digraph. |
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| 361 | /// |
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| 362 | ///This function can be called more than once. In case of a repeated |
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| 363 | ///call, the previous snapshot gets lost. |
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| 364 | ///\param _g The digraph we make the snapshot of. |
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| 365 | void save(SmartDigraph &graph) |
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| 366 | { |
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| 367 | _graph=&graph; |
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| 368 | node_num=_graph->nodes.size(); |
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| 369 | arc_num=_graph->arcs.size(); |
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| 370 | } |
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| 371 | |
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| 372 | ///Undo the changes until a snapshot. |
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| 373 | |
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| 374 | ///Undo the changes until a snapshot created by save(). |
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| 375 | /// |
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| 376 | ///\note After you restored a state, you cannot restore |
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| 377 | ///a later state, in other word you cannot add again the arcs deleted |
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| 378 | ///by restore(). |
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| 379 | void restore() |
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| 380 | { |
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| 381 | _graph->restoreSnapshot(*this); |
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| 382 | } |
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| 383 | }; |
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| 384 | }; |
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| 385 | |
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| 386 | |
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| 387 | class SmartGraphBase { |
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| 388 | |
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| 389 | protected: |
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| 390 | |
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| 391 | struct NodeT { |
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| 392 | int first_out; |
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| 393 | }; |
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| 394 | |
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| 395 | struct ArcT { |
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| 396 | int target; |
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| 397 | int next_out; |
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| 398 | }; |
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| 399 | |
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| 400 | std::vector<NodeT> nodes; |
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| 401 | std::vector<ArcT> arcs; |
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| 402 | |
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| 403 | int first_free_arc; |
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| 404 | |
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| 405 | public: |
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| 406 | |
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| 407 | typedef SmartGraphBase Digraph; |
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| 408 | |
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| 409 | class Node; |
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| 410 | class Arc; |
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| 411 | class Edge; |
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| 412 | |
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| 413 | class Node { |
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| 414 | friend class SmartGraphBase; |
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| 415 | protected: |
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| 416 | |
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| 417 | int _id; |
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| 418 | explicit Node(int id) { _id = id;} |
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| 419 | |
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| 420 | public: |
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| 421 | Node() {} |
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| 422 | Node (Invalid) { _id = -1; } |
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| 423 | bool operator==(const Node& node) const {return _id == node._id;} |
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| 424 | bool operator!=(const Node& node) const {return _id != node._id;} |
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| 425 | bool operator<(const Node& node) const {return _id < node._id;} |
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| 426 | }; |
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| 427 | |
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| 428 | class Edge { |
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| 429 | friend class SmartGraphBase; |
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| 430 | protected: |
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| 431 | |
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| 432 | int _id; |
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| 433 | explicit Edge(int id) { _id = id;} |
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| 434 | |
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| 435 | public: |
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| 436 | Edge() {} |
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| 437 | Edge (Invalid) { _id = -1; } |
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| 438 | bool operator==(const Edge& arc) const {return _id == arc._id;} |
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| 439 | bool operator!=(const Edge& arc) const {return _id != arc._id;} |
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| 440 | bool operator<(const Edge& arc) const {return _id < arc._id;} |
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| 441 | }; |
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| 442 | |
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| 443 | class Arc { |
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| 444 | friend class SmartGraphBase; |
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| 445 | protected: |
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| 446 | |
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| 447 | int _id; |
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| 448 | explicit Arc(int id) { _id = id;} |
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| 449 | |
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| 450 | public: |
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| 451 | operator Edge() const { return edgeFromId(_id / 2); } |
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| 452 | |
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| 453 | Arc() {} |
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| 454 | Arc (Invalid) { _id = -1; } |
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| 455 | bool operator==(const Arc& arc) const {return _id == arc._id;} |
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| 456 | bool operator!=(const Arc& arc) const {return _id != arc._id;} |
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| 457 | bool operator<(const Arc& arc) const {return _id < arc._id;} |
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| 458 | }; |
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| 459 | |
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| 460 | |
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| 461 | |
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| 462 | SmartGraphBase() |
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| 463 | : nodes(), arcs() {} |
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| 464 | |
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| 465 | |
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| 466 | int maxNodeId() const { return nodes.size()-1; } |
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| 467 | int maxEdgeId() const { return arcs.size() / 2 - 1; } |
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| 468 | int maxArcId() const { return arcs.size()-1; } |
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| 469 | |
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| 470 | Node source(Arc e) const { return Node(arcs[e._id ^ 1].target); } |
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| 471 | Node target(Arc e) const { return Node(arcs[e._id].target); } |
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| 472 | |
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[125] | 473 | Node u(Edge e) const { return Node(arcs[2 * e._id].target); } |
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| 474 | Node v(Edge e) const { return Node(arcs[2 * e._id + 1].target); } |
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[109] | 475 | |
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| 476 | static bool direction(Arc e) { |
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| 477 | return (e._id & 1) == 1; |
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| 478 | } |
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| 479 | |
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| 480 | static Arc direct(Edge e, bool d) { |
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| 481 | return Arc(e._id * 2 + (d ? 1 : 0)); |
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| 482 | } |
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| 483 | |
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| 484 | void first(Node& node) const { |
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| 485 | node._id = nodes.size() - 1; |
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| 486 | } |
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| 487 | |
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| 488 | void next(Node& node) const { |
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| 489 | --node._id; |
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| 490 | } |
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| 491 | |
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| 492 | void first(Arc& arc) const { |
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| 493 | arc._id = arcs.size() - 1; |
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| 494 | } |
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| 495 | |
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| 496 | void next(Arc& arc) const { |
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| 497 | --arc._id; |
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| 498 | } |
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| 499 | |
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| 500 | void first(Edge& arc) const { |
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| 501 | arc._id = arcs.size() / 2 - 1; |
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| 502 | } |
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| 503 | |
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| 504 | void next(Edge& arc) const { |
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| 505 | --arc._id; |
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| 506 | } |
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| 507 | |
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| 508 | void firstOut(Arc &arc, const Node& v) const { |
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| 509 | arc._id = nodes[v._id].first_out; |
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| 510 | } |
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| 511 | void nextOut(Arc &arc) const { |
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| 512 | arc._id = arcs[arc._id].next_out; |
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| 513 | } |
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| 514 | |
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| 515 | void firstIn(Arc &arc, const Node& v) const { |
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| 516 | arc._id = ((nodes[v._id].first_out) ^ 1); |
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| 517 | if (arc._id == -2) arc._id = -1; |
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| 518 | } |
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| 519 | void nextIn(Arc &arc) const { |
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| 520 | arc._id = ((arcs[arc._id ^ 1].next_out) ^ 1); |
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| 521 | if (arc._id == -2) arc._id = -1; |
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| 522 | } |
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| 523 | |
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| 524 | void firstInc(Edge &arc, bool& d, const Node& v) const { |
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| 525 | int de = nodes[v._id].first_out; |
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| 526 | if (de != -1) { |
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| 527 | arc._id = de / 2; |
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| 528 | d = ((de & 1) == 1); |
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| 529 | } else { |
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| 530 | arc._id = -1; |
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| 531 | d = true; |
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| 532 | } |
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| 533 | } |
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| 534 | void nextInc(Edge &arc, bool& d) const { |
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| 535 | int de = (arcs[(arc._id * 2) | (d ? 1 : 0)].next_out); |
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| 536 | if (de != -1) { |
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| 537 | arc._id = de / 2; |
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| 538 | d = ((de & 1) == 1); |
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| 539 | } else { |
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| 540 | arc._id = -1; |
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| 541 | d = true; |
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| 542 | } |
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| 543 | } |
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| 544 | |
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| 545 | static int id(Node v) { return v._id; } |
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| 546 | static int id(Arc e) { return e._id; } |
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| 547 | static int id(Edge e) { return e._id; } |
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| 548 | |
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| 549 | static Node nodeFromId(int id) { return Node(id);} |
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| 550 | static Arc arcFromId(int id) { return Arc(id);} |
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| 551 | static Edge edgeFromId(int id) { return Edge(id);} |
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| 552 | |
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| 553 | Node addNode() { |
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| 554 | int n = nodes.size(); |
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| 555 | nodes.push_back(NodeT()); |
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| 556 | nodes[n].first_out = -1; |
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| 557 | |
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| 558 | return Node(n); |
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| 559 | } |
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| 560 | |
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| 561 | Edge addArc(Node u, Node v) { |
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| 562 | int n = arcs.size(); |
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| 563 | arcs.push_back(ArcT()); |
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| 564 | arcs.push_back(ArcT()); |
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| 565 | |
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| 566 | arcs[n].target = u._id; |
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| 567 | arcs[n | 1].target = v._id; |
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| 568 | |
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| 569 | arcs[n].next_out = nodes[v._id].first_out; |
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| 570 | nodes[v._id].first_out = n; |
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| 571 | |
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| 572 | arcs[n | 1].next_out = nodes[u._id].first_out; |
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| 573 | nodes[u._id].first_out = (n | 1); |
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| 574 | |
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| 575 | return Edge(n / 2); |
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| 576 | } |
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| 577 | |
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| 578 | void clear() { |
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| 579 | arcs.clear(); |
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| 580 | nodes.clear(); |
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| 581 | } |
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| 582 | |
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| 583 | }; |
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| 584 | |
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| 585 | typedef GraphExtender<SmartGraphBase> ExtendedSmartGraphBase; |
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| 586 | |
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| 587 | /// \ingroup graphs |
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| 588 | /// |
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| 589 | /// \brief A smart undirected graph class. |
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| 590 | /// |
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| 591 | /// This is a simple and fast graph implementation. |
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| 592 | /// It is also quite memory efficient, but at the price |
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| 593 | /// that <b> it does support only limited (only stack-like) |
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| 594 | /// node and arc deletions</b>. |
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| 595 | /// Except from this it conforms to |
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| 596 | /// the \ref concepts::Graph "Graph concept". |
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| 597 | /// |
---|
| 598 | /// It also has an |
---|
| 599 | /// important extra feature that |
---|
| 600 | /// its maps are real \ref concepts::ReferenceMap "reference map"s. |
---|
| 601 | /// |
---|
| 602 | /// \sa concepts::Graph. |
---|
| 603 | /// |
---|
| 604 | class SmartGraph : public ExtendedSmartGraphBase { |
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| 605 | private: |
---|
| 606 | |
---|
| 607 | ///SmartGraph is \e not copy constructible. Use GraphCopy() instead. |
---|
| 608 | |
---|
| 609 | ///SmartGraph is \e not copy constructible. Use GraphCopy() instead. |
---|
| 610 | /// |
---|
| 611 | SmartGraph(const SmartGraph &) : ExtendedSmartGraphBase() {}; |
---|
| 612 | |
---|
| 613 | ///\brief Assignment of SmartGraph to another one is \e not allowed. |
---|
| 614 | ///Use GraphCopy() instead. |
---|
| 615 | |
---|
| 616 | ///Assignment of SmartGraph to another one is \e not allowed. |
---|
| 617 | ///Use GraphCopy() instead. |
---|
| 618 | void operator=(const SmartGraph &) {} |
---|
| 619 | |
---|
| 620 | public: |
---|
| 621 | |
---|
| 622 | typedef ExtendedSmartGraphBase Parent; |
---|
| 623 | |
---|
| 624 | /// Constructor |
---|
| 625 | |
---|
| 626 | /// Constructor. |
---|
| 627 | /// |
---|
| 628 | SmartGraph() {} |
---|
| 629 | |
---|
| 630 | ///Add a new node to the graph. |
---|
| 631 | |
---|
| 632 | /// \return the new node. |
---|
| 633 | /// |
---|
| 634 | Node addNode() { return Parent::addNode(); } |
---|
| 635 | |
---|
| 636 | ///Add a new edge to the graph. |
---|
| 637 | |
---|
| 638 | ///Add a new edge to the graph with node \c s |
---|
| 639 | ///and \c t. |
---|
| 640 | ///\return the new edge. |
---|
| 641 | Edge addEdge(const Node& s, const Node& t) { |
---|
| 642 | return Parent::addArc(s, t); |
---|
| 643 | } |
---|
| 644 | |
---|
| 645 | ///Clear the graph. |
---|
| 646 | |
---|
| 647 | ///Erase all the nodes and edges from the graph. |
---|
| 648 | /// |
---|
| 649 | void clear() { |
---|
| 650 | Parent::clear(); |
---|
| 651 | } |
---|
| 652 | |
---|
| 653 | public: |
---|
| 654 | |
---|
| 655 | class Snapshot; |
---|
| 656 | |
---|
| 657 | protected: |
---|
| 658 | |
---|
| 659 | void saveSnapshot(Snapshot &s) |
---|
| 660 | { |
---|
| 661 | s._graph = this; |
---|
| 662 | s.node_num = nodes.size(); |
---|
| 663 | s.arc_num = arcs.size(); |
---|
| 664 | } |
---|
| 665 | |
---|
| 666 | void restoreSnapshot(const Snapshot &s) |
---|
| 667 | { |
---|
| 668 | while(s.arc_num<arcs.size()) { |
---|
| 669 | int n=arcs.size()-1; |
---|
| 670 | Edge arc=edgeFromId(n/2); |
---|
| 671 | Parent::notifier(Edge()).erase(arc); |
---|
| 672 | std::vector<Arc> dir; |
---|
| 673 | dir.push_back(arcFromId(n)); |
---|
| 674 | dir.push_back(arcFromId(n-1)); |
---|
| 675 | Parent::notifier(Arc()).erase(dir); |
---|
| 676 | nodes[arcs[n].target].first_out=arcs[n].next_out; |
---|
| 677 | nodes[arcs[n-1].target].first_out=arcs[n-1].next_out; |
---|
| 678 | arcs.pop_back(); |
---|
| 679 | arcs.pop_back(); |
---|
| 680 | } |
---|
| 681 | while(s.node_num<nodes.size()) { |
---|
| 682 | int n=nodes.size()-1; |
---|
| 683 | Node node = nodeFromId(n); |
---|
| 684 | Parent::notifier(Node()).erase(node); |
---|
| 685 | nodes.pop_back(); |
---|
| 686 | } |
---|
| 687 | } |
---|
| 688 | |
---|
| 689 | public: |
---|
| 690 | |
---|
| 691 | ///Class to make a snapshot of the digraph and to restrore to it later. |
---|
| 692 | |
---|
| 693 | ///Class to make a snapshot of the digraph and to restrore to it later. |
---|
| 694 | /// |
---|
| 695 | ///The newly added nodes and arcs can be removed using the |
---|
| 696 | ///restore() function. |
---|
| 697 | /// |
---|
| 698 | ///\note After you restore a state, you cannot restore |
---|
| 699 | ///a later state, in other word you cannot add again the arcs deleted |
---|
| 700 | ///by restore() using another one Snapshot instance. |
---|
| 701 | /// |
---|
| 702 | ///\warning If you do not use correctly the snapshot that can cause |
---|
| 703 | ///either broken program, invalid state of the digraph, valid but |
---|
| 704 | ///not the restored digraph or no change. Because the runtime performance |
---|
| 705 | ///the validity of the snapshot is not stored. |
---|
| 706 | class Snapshot |
---|
| 707 | { |
---|
| 708 | SmartGraph *_graph; |
---|
| 709 | protected: |
---|
| 710 | friend class SmartGraph; |
---|
| 711 | unsigned int node_num; |
---|
| 712 | unsigned int arc_num; |
---|
| 713 | public: |
---|
| 714 | ///Default constructor. |
---|
| 715 | |
---|
| 716 | ///Default constructor. |
---|
| 717 | ///To actually make a snapshot you must call save(). |
---|
| 718 | /// |
---|
| 719 | Snapshot() : _graph(0) {} |
---|
| 720 | ///Constructor that immediately makes a snapshot |
---|
| 721 | |
---|
| 722 | ///This constructor immediately makes a snapshot of the digraph. |
---|
| 723 | ///\param g The digraph we make a snapshot of. |
---|
| 724 | Snapshot(SmartGraph &graph) { |
---|
| 725 | graph.saveSnapshot(*this); |
---|
| 726 | } |
---|
| 727 | |
---|
| 728 | ///Make a snapshot. |
---|
| 729 | |
---|
| 730 | ///Make a snapshot of the graph. |
---|
| 731 | /// |
---|
| 732 | ///This function can be called more than once. In case of a repeated |
---|
| 733 | ///call, the previous snapshot gets lost. |
---|
| 734 | ///\param g The digraph we make the snapshot of. |
---|
| 735 | void save(SmartGraph &graph) |
---|
| 736 | { |
---|
| 737 | graph.saveSnapshot(*this); |
---|
| 738 | } |
---|
| 739 | |
---|
| 740 | ///Undo the changes until a snapshot. |
---|
| 741 | |
---|
| 742 | ///Undo the changes until a snapshot created by save(). |
---|
| 743 | /// |
---|
| 744 | ///\note After you restored a state, you cannot restore |
---|
| 745 | ///a later state, in other word you cannot add again the arcs deleted |
---|
| 746 | ///by restore(). |
---|
| 747 | void restore() |
---|
| 748 | { |
---|
| 749 | _graph->restoreSnapshot(*this); |
---|
| 750 | } |
---|
| 751 | }; |
---|
| 752 | }; |
---|
| 753 | |
---|
| 754 | } //namespace lemon |
---|
| 755 | |
---|
| 756 | |
---|
| 757 | #endif //LEMON_SMART_GRAPH_H |
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