| 1 | // -*- c++ -*- |
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| 2 | #ifndef EDMONDS_KARP_H |
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| 3 | #define EDMONDS_KARP_H |
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| 4 | |
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| 5 | #include <algorithm> |
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| 6 | #include <list> |
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| 7 | #include <iterator> |
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| 8 | |
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| 9 | #include <bfs_iterator.h> |
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| 10 | #include <invalid.h> |
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| 11 | |
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| 12 | namespace hugo { |
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| 13 | |
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| 14 | template<typename Graph, typename Number, typename FlowMap, typename CapacityMap> |
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| 15 | class ResGraph { |
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| 16 | public: |
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| 17 | typedef typename Graph::Node Node; |
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| 18 | typedef typename Graph::NodeIt NodeIt; |
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| 19 | private: |
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| 20 | typedef typename Graph::SymEdgeIt OldSymEdgeIt; |
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| 21 | const Graph& G; |
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| 22 | FlowMap& flow; |
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| 23 | const CapacityMap& capacity; |
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| 24 | public: |
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| 25 | ResGraph(const Graph& _G, FlowMap& _flow, |
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| 26 | const CapacityMap& _capacity) : |
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| 27 | G(_G), flow(_flow), capacity(_capacity) { } |
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| 28 | |
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| 29 | class Edge; |
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| 30 | class OutEdgeIt; |
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| 31 | friend class Edge; |
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| 32 | friend class OutEdgeIt; |
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| 33 | |
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| 34 | class Edge { |
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| 35 | friend class ResGraph<Graph, Number, FlowMap, CapacityMap>; |
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| 36 | protected: |
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| 37 | const ResGraph<Graph, Number, FlowMap, CapacityMap>* resG; |
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| 38 | OldSymEdgeIt sym; |
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| 39 | public: |
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| 40 | Edge() { } |
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| 41 | //Edge(const Edge& e) : resG(e.resG), sym(e.sym) { } |
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| 42 | Number free() const { |
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| 43 | if (resG->G.aNode(sym)==resG->G.tail(sym)) { |
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| 44 | return (resG->capacity.get(sym)-resG->flow.get(sym)); |
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| 45 | } else { |
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| 46 | return (resG->flow.get(sym)); |
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| 47 | } |
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| 48 | } |
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| 49 | bool valid() const { return sym.valid(); } |
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| 50 | void augment(Number a) const { |
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| 51 | if (resG->G.aNode(sym)==resG->G.tail(sym)) { |
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| 52 | resG->flow.set(sym, resG->flow.get(sym)+a); |
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| 53 | //resG->flow[sym]+=a; |
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| 54 | } else { |
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| 55 | resG->flow.set(sym, resG->flow.get(sym)-a); |
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| 56 | //resG->flow[sym]-=a; |
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| 57 | } |
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| 58 | } |
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| 59 | }; |
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| 60 | |
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| 61 | class OutEdgeIt : public Edge { |
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| 62 | friend class ResGraph<Graph, Number, FlowMap, CapacityMap>; |
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| 63 | public: |
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| 64 | OutEdgeIt() { } |
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| 65 | //OutEdgeIt(const OutEdgeIt& e) { resG=e.resG; sym=e.sym; } |
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| 66 | private: |
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| 67 | OutEdgeIt(const ResGraph<Graph, Number, FlowMap, CapacityMap>& _resG, Node v) { |
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| 68 | resG=&_resG; |
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| 69 | sym=resG->G.template first<OldSymEdgeIt>(v); |
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| 70 | while( sym.valid() && !(free()>0) ) { ++sym; } |
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| 71 | } |
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| 72 | public: |
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| 73 | OutEdgeIt& operator++() { |
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| 74 | ++sym; |
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| 75 | while( sym.valid() && !(free()>0) ) { ++sym; } |
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| 76 | return *this; |
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| 77 | } |
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| 78 | }; |
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| 79 | |
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| 80 | void /*getF*/first(OutEdgeIt& e, Node v) const { |
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| 81 | e=OutEdgeIt(*this, v); |
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| 82 | } |
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| 83 | void /*getF*/first(NodeIt& v) const { G./*getF*/first(v); } |
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| 84 | |
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| 85 | template< typename It > |
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| 86 | It first() const { |
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| 87 | It e; |
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| 88 | /*getF*/first(e); |
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| 89 | return e; |
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| 90 | } |
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| 91 | |
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| 92 | template< typename It > |
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| 93 | It first(Node v) const { |
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| 94 | It e; |
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| 95 | /*getF*/first(e, v); |
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| 96 | return e; |
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| 97 | } |
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| 98 | |
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| 99 | Node tail(Edge e) const { return G.aNode(e.sym); } |
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| 100 | Node head(Edge e) const { return G.bNode(e.sym); } |
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| 101 | |
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| 102 | Node aNode(OutEdgeIt e) const { return G.aNode(e.sym); } |
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| 103 | Node bNode(OutEdgeIt e) const { return G.bNode(e.sym); } |
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| 104 | |
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| 105 | int id(Node v) const { return G.id(v); } |
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| 106 | |
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| 107 | template <typename S> |
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| 108 | class NodeMap { |
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| 109 | typename Graph::NodeMap<S> node_map; |
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| 110 | public: |
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| 111 | NodeMap(const ResGraph<Graph, Number, FlowMap, CapacityMap>& _G) : node_map(_G.G) { } |
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| 112 | NodeMap(const ResGraph<Graph, Number, FlowMap, CapacityMap>& _G, S a) : node_map(_G.G, a) { } |
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| 113 | void set(Node nit, S a) { node_map.set(nit, a); } |
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| 114 | S get(Node nit) const { return node_map.get(nit); } |
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| 115 | S& operator[](Node nit) { return node_map[nit]; } |
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| 116 | const S& operator[](Node nit) const { return node_map[nit]; } |
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| 117 | }; |
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| 118 | |
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| 119 | }; |
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| 120 | |
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| 121 | |
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| 122 | template<typename Graph, typename Number, typename FlowMap, typename CapacityMap> |
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| 123 | class ResGraph2 { |
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| 124 | public: |
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| 125 | typedef typename Graph::Node Node; |
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| 126 | typedef typename Graph::NodeIt NodeIt; |
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| 127 | private: |
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| 128 | //typedef typename Graph::SymEdgeIt OldSymEdgeIt; |
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| 129 | typedef typename Graph::OutEdgeIt OldOutEdgeIt; |
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| 130 | typedef typename Graph::InEdgeIt OldInEdgeIt; |
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| 131 | |
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| 132 | const Graph& G; |
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| 133 | FlowMap& flow; |
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| 134 | const CapacityMap& capacity; |
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| 135 | public: |
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| 136 | ResGraph2(const Graph& _G, FlowMap& _flow, |
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| 137 | const CapacityMap& _capacity) : |
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| 138 | G(_G), flow(_flow), capacity(_capacity) { } |
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| 139 | |
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| 140 | class Edge; |
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| 141 | class OutEdgeIt; |
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| 142 | friend class Edge; |
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| 143 | friend class OutEdgeIt; |
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| 144 | |
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| 145 | class Edge { |
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| 146 | friend class ResGraph2<Graph, Number, FlowMap, CapacityMap>; |
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| 147 | protected: |
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| 148 | const ResGraph2<Graph, Number, FlowMap, CapacityMap>* resG; |
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| 149 | //OldSymEdgeIt sym; |
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| 150 | OldOutEdgeIt out; |
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| 151 | OldInEdgeIt in; |
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| 152 | bool out_or_in; //true, iff out |
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| 153 | public: |
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| 154 | Edge() : out_or_in(true) { } |
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| 155 | Number free() const { |
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| 156 | if (out_or_in) { |
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| 157 | return (resG->capacity.get(out)-resG->flow.get(out)); |
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| 158 | } else { |
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| 159 | return (resG->flow.get(in)); |
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| 160 | } |
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| 161 | } |
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| 162 | bool valid() const { |
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| 163 | return out_or_in && out.valid() || in.valid(); } |
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| 164 | void augment(Number a) const { |
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| 165 | if (out_or_in) { |
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| 166 | resG->flow.set(out, resG->flow.get(out)+a); |
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| 167 | } else { |
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| 168 | resG->flow.set(in, resG->flow.get(in)-a); |
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| 169 | } |
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| 170 | } |
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| 171 | }; |
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| 172 | |
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| 173 | class OutEdgeIt : public Edge { |
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| 174 | friend class ResGraph2<Graph, Number, FlowMap, CapacityMap>; |
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| 175 | public: |
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| 176 | OutEdgeIt() { } |
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| 177 | private: |
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| 178 | OutEdgeIt(const ResGraph2<Graph, Number, FlowMap, CapacityMap>& _resG, Node v) { |
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| 179 | resG=&_resG; |
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| 180 | out=resG->G.template first<OldOutEdgeIt>(v); |
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| 181 | while( out.valid() && !(free()>0) ) { ++out; } |
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| 182 | if (!out.valid()) { |
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| 183 | out_or_in=0; |
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| 184 | in=resG->G.template first<OldInEdgeIt>(v); |
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| 185 | while( in.valid() && !(free()>0) ) { ++in; } |
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| 186 | } |
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| 187 | } |
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| 188 | public: |
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| 189 | OutEdgeIt& operator++() { |
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| 190 | if (out_or_in) { |
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| 191 | Node v=resG->G.aNode(out); |
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| 192 | ++out; |
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| 193 | while( out.valid() && !(free()>0) ) { ++out; } |
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| 194 | if (!out.valid()) { |
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| 195 | out_or_in=0; |
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| 196 | in=resG->G.template first<OldInEdgeIt>(v); |
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| 197 | while( in.valid() && !(free()>0) ) { ++in; } |
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| 198 | } |
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| 199 | } else { |
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| 200 | ++in; |
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| 201 | while( in.valid() && !(free()>0) ) { ++in; } |
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| 202 | } |
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| 203 | return *this; |
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| 204 | } |
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| 205 | }; |
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| 206 | |
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| 207 | void /*getF*/first(OutEdgeIt& e, Node v) const { |
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| 208 | e=OutEdgeIt(*this, v); |
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| 209 | } |
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| 210 | void /*getF*/first(NodeIt& v) const { G./*getF*/first(v); } |
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| 211 | |
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| 212 | template< typename It > |
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| 213 | It first() const { |
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| 214 | It e; |
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| 215 | /*getF*/first(e); |
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| 216 | return e; |
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| 217 | } |
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| 218 | |
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| 219 | template< typename It > |
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| 220 | It first(Node v) const { |
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| 221 | It e; |
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| 222 | /*getF*/first(e, v); |
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| 223 | return e; |
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| 224 | } |
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| 225 | |
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| 226 | Node tail(Edge e) const { |
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| 227 | return ((e.out_or_in) ? G.aNode(e.out) : G.aNode(e.in)); } |
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| 228 | Node head(Edge e) const { |
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| 229 | return ((e.out_or_in) ? G.bNode(e.out) : G.bNode(e.in)); } |
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| 230 | |
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| 231 | Node aNode(OutEdgeIt e) const { |
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| 232 | return ((e.out_or_in) ? G.aNode(e.out) : G.aNode(e.in)); } |
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| 233 | Node bNode(OutEdgeIt e) const { |
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| 234 | return ((e.out_or_in) ? G.bNode(e.out) : G.bNode(e.in)); } |
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| 235 | |
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| 236 | int id(Node v) const { return G.id(v); } |
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| 237 | |
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| 238 | template <typename S> |
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| 239 | class NodeMap { |
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| 240 | typename Graph::NodeMap<S> node_map; |
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| 241 | public: |
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| 242 | NodeMap(const ResGraph2<Graph, Number, FlowMap, CapacityMap>& _G) : node_map(_G.G) { } |
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| 243 | NodeMap(const ResGraph2<Graph, Number, FlowMap, CapacityMap>& _G, S a) : node_map(_G.G, a) { } |
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| 244 | void set(Node nit, S a) { node_map.set(nit, a); } |
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| 245 | S get(Node nit) const { return node_map.get(nit); } |
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| 246 | }; |
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| 247 | }; |
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| 248 | |
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| 249 | |
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| 250 | template <typename Graph, typename Number, typename FlowMap, typename CapacityMap> |
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| 251 | class MaxFlow { |
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| 252 | public: |
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| 253 | typedef typename Graph::Node Node; |
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| 254 | typedef typename Graph::Edge Edge; |
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| 255 | typedef typename Graph::EdgeIt EdgeIt; |
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| 256 | typedef typename Graph::OutEdgeIt OutEdgeIt; |
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| 257 | typedef typename Graph::InEdgeIt InEdgeIt; |
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| 258 | |
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| 259 | private: |
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| 260 | const Graph* G; |
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| 261 | Node s; |
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| 262 | Node t; |
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| 263 | FlowMap* flow; |
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| 264 | const CapacityMap* capacity; |
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| 265 | typedef ResGraphWrapper<Graph, Number, FlowMap, CapacityMap > AugGraph; |
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| 266 | typedef typename AugGraph::OutEdgeIt AugOutEdgeIt; |
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| 267 | typedef typename AugGraph::Edge AugEdge; |
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| 268 | |
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| 269 | public: |
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| 270 | MaxFlow(const Graph& _G, Node _s, Node _t, FlowMap& _flow, const CapacityMap& _capacity) : |
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| 271 | G(&_G), s(_s), t(_t), flow(&_flow), capacity(&_capacity) { } |
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| 272 | bool augmentOnShortestPath() { |
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| 273 | AugGraph res_graph(*G, *flow, *capacity); |
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| 274 | bool _augment=false; |
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| 275 | |
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| 276 | typedef typename AugGraph::NodeMap<bool> ReachedMap; |
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| 277 | BfsIterator5< AugGraph, /*AugOutEdgeIt,*/ ReachedMap > res_bfs(res_graph); |
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| 278 | res_bfs.pushAndSetReached(s); |
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| 279 | |
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| 280 | typename AugGraph::NodeMap<AugEdge> pred(res_graph); |
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| 281 | pred.set(s, AugEdge(INVALID)); |
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| 282 | |
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| 283 | typename AugGraph::NodeMap<Number> free(res_graph); |
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| 284 | |
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| 285 | //searching for augmenting path |
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| 286 | while ( !res_bfs.finished() ) { |
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| 287 | AugOutEdgeIt e=res_bfs; |
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| 288 | if (res_graph.valid(e) && res_bfs.isBNodeNewlyReached()) { |
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| 289 | Node v=res_graph.tail(e); |
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| 290 | Node w=res_graph.head(e); |
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| 291 | pred.set(w, e); |
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| 292 | if (res_graph.valid(pred.get(v))) { |
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| 293 | free.set(w, std::min(free.get(v), res_graph.free(e))); |
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| 294 | } else { |
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| 295 | free.set(w, res_graph.free(e)); |
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| 296 | } |
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| 297 | if (res_graph.head(e)==t) { _augment=true; break; } |
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| 298 | } |
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| 299 | |
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| 300 | ++res_bfs; |
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| 301 | } //end of searching augmenting path |
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| 302 | |
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| 303 | if (_augment) { |
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| 304 | Node n=t; |
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| 305 | Number augment_value=free.get(t); |
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| 306 | while (res_graph.valid(pred.get(n))) { |
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| 307 | AugEdge e=pred.get(n); |
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| 308 | res_graph.augment(e, augment_value); |
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| 309 | n=res_graph.tail(e); |
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| 310 | } |
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| 311 | } |
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| 312 | |
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| 313 | return _augment; |
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| 314 | } |
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| 315 | |
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| 316 | template<typename MutableGraph> bool augmentOnBlockingFlow() { |
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| 317 | bool _augment=false; |
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| 318 | |
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| 319 | AugGraph res_graph(*G, *flow, *capacity); |
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| 320 | |
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| 321 | typedef typename AugGraph::NodeMap<bool> ReachedMap; |
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| 322 | BfsIterator5< AugGraph /*, AugOutEdgeIt*/, ReachedMap > bfs(res_graph); |
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| 323 | |
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| 324 | bfs.pushAndSetReached(s); |
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| 325 | typename AugGraph::NodeMap<int> dist(res_graph); //filled up with 0's |
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| 326 | while ( !bfs.finished() ) { |
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| 327 | AugOutEdgeIt e=bfs; |
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| 328 | if (res_graph.valid(e) && bfs.isBNodeNewlyReached()) { |
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| 329 | dist.set(res_graph.head(e), dist.get(res_graph.tail(e))+1); |
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| 330 | } |
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| 331 | |
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| 332 | ++bfs; |
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| 333 | } //computing distances from s in the residual graph |
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| 334 | |
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| 335 | MutableGraph F; |
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| 336 | typename AugGraph::NodeMap<typename MutableGraph::Node> |
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| 337 | res_graph_to_F(res_graph); |
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| 338 | for(typename AugGraph::NodeIt n=res_graph.template first<typename AugGraph::NodeIt>(); res_graph.valid(n); res_graph.next(n)) { |
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| 339 | res_graph_to_F.set(n, F.addNode()); |
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| 340 | } |
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| 341 | |
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| 342 | typename MutableGraph::Node sF=res_graph_to_F.get(s); |
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| 343 | typename MutableGraph::Node tF=res_graph_to_F.get(t); |
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| 344 | |
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| 345 | typename MutableGraph::EdgeMap<AugEdge> original_edge(F); |
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| 346 | typename MutableGraph::EdgeMap<Number> residual_capacity(F); |
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| 347 | |
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| 348 | //Making F to the graph containing the edges of the residual graph |
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| 349 | //which are in some shortest paths |
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| 350 | for(typename AugGraph::EdgeIt e=res_graph.template first<typename AugGraph::EdgeIt>(); res_graph.valid(e); res_graph.next(e)) { |
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| 351 | if (dist.get(res_graph.head(e))==dist.get(res_graph.tail(e))+1) { |
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| 352 | typename MutableGraph::Edge f=F.addEdge(res_graph_to_F.get(res_graph.tail(e)), res_graph_to_F.get(res_graph.head(e))); |
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| 353 | original_edge.update(); |
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| 354 | original_edge.set(f, e); |
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| 355 | residual_capacity.update(); |
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| 356 | residual_capacity.set(f, res_graph.free(e)); |
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| 357 | } |
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| 358 | } |
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| 359 | |
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| 360 | bool __augment=true; |
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| 361 | |
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| 362 | while (__augment) { |
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| 363 | __augment=false; |
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| 364 | //computing blocking flow with dfs |
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| 365 | typedef typename TrivGraphWrapper<MutableGraph>::NodeMap<bool> BlockingReachedMap; |
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| 366 | DfsIterator5< TrivGraphWrapper<MutableGraph>/*, typename MutableGraph::OutEdgeIt*/, BlockingReachedMap > dfs(F); |
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| 367 | typename MutableGraph::NodeMap<typename MutableGraph::Edge> pred(F); |
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| 368 | pred.set(sF, typename MutableGraph::Edge(INVALID)); |
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| 369 | //invalid iterators for sources |
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| 370 | |
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| 371 | typename MutableGraph::NodeMap<Number> free(F); |
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| 372 | |
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| 373 | dfs.pushAndSetReached(sF); |
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| 374 | while (!dfs.finished()) { |
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| 375 | ++dfs; |
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| 376 | if (F.valid(typename MutableGraph::OutEdgeIt(dfs))) { |
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| 377 | if (dfs.isBNodeNewlyReached()) { |
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| 378 | typename MutableGraph::Node v=F.aNode(dfs); |
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| 379 | typename MutableGraph::Node w=F.bNode(dfs); |
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| 380 | pred.set(w, dfs); |
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| 381 | if (F.valid(pred.get(v))) { |
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| 382 | free.set(w, std::min(free.get(v), residual_capacity.get(dfs))); |
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| 383 | } else { |
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| 384 | free.set(w, residual_capacity.get(dfs)); |
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| 385 | } |
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| 386 | if (w==tF) { |
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| 387 | __augment=true; |
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| 388 | _augment=true; |
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| 389 | break; |
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| 390 | } |
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| 391 | |
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| 392 | } else { |
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| 393 | F.erase(typename MutableGraph::OutEdgeIt(dfs)); |
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| 394 | } |
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| 395 | } |
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| 396 | } |
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| 397 | |
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| 398 | if (__augment) { |
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| 399 | typename MutableGraph::Node n=tF; |
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| 400 | Number augment_value=free.get(tF); |
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| 401 | while (F.valid(pred.get(n))) { |
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| 402 | typename MutableGraph::Edge e=pred.get(n); |
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| 403 | res_graph.augment(original_edge.get(e), augment_value); |
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| 404 | n=F.tail(e); |
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| 405 | if (residual_capacity.get(e)==augment_value) |
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| 406 | F.erase(e); |
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| 407 | else |
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| 408 | residual_capacity.set(e, residual_capacity.get(e)-augment_value); |
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| 409 | } |
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| 410 | } |
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| 411 | |
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| 412 | } |
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| 413 | |
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| 414 | return _augment; |
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| 415 | } |
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| 416 | template<typename MutableGraph> bool augmentOnBlockingFlow1() { |
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| 417 | bool _augment=false; |
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| 418 | |
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| 419 | AugGraph res_graph(*G, *flow, *capacity); |
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| 420 | |
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| 421 | //bfs for distances on the residual graph |
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| 422 | typedef typename AugGraph::NodeMap<bool> ReachedMap; |
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| 423 | BfsIterator5< AugGraph /*, AugOutEdgeIt*/, ReachedMap > bfs(res_graph); |
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| 424 | bfs.pushAndSetReached(s); |
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| 425 | typename AugGraph::NodeMap<int> dist(res_graph); //filled up with 0's |
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| 426 | |
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| 427 | //F will contain the physical copy of the residual graph |
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| 428 | //with the set of edges which areon shortest paths |
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| 429 | MutableGraph F; |
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| 430 | typename AugGraph::NodeMap<typename MutableGraph::Node> |
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| 431 | res_graph_to_F(res_graph); |
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| 432 | for(typename AugGraph::NodeIt n=res_graph.template first<typename AugGraph::NodeIt>(); res_graph.valid(n); res_graph.next(n)) { |
|---|
| 433 | res_graph_to_F.set(n, F.addNode()); |
|---|
| 434 | } |
|---|
| 435 | typename MutableGraph::Node sF=res_graph_to_F.get(s); |
|---|
| 436 | typename MutableGraph::Node tF=res_graph_to_F.get(t); |
|---|
| 437 | typename MutableGraph::EdgeMap<AugEdge> original_edge(F); |
|---|
| 438 | typename MutableGraph::EdgeMap<Number> residual_capacity(F); |
|---|
| 439 | |
|---|
| 440 | while ( !bfs.finished() ) { |
|---|
| 441 | AugOutEdgeIt e=bfs; |
|---|
| 442 | if (res_graph.valid(e)) { |
|---|
| 443 | if (bfs.isBNodeNewlyReached()) { |
|---|
| 444 | dist.set(res_graph.head(e), dist.get(res_graph.tail(e))+1); |
|---|
| 445 | typename MutableGraph::Edge f=F.addEdge(res_graph_to_F.get(res_graph.tail(e)), res_graph_to_F.get(res_graph.head(e))); |
|---|
| 446 | original_edge.update(); |
|---|
| 447 | original_edge.set(f, e); |
|---|
| 448 | residual_capacity.update(); |
|---|
| 449 | residual_capacity.set(f, res_graph.free(e)); |
|---|
| 450 | } else { |
|---|
| 451 | if (dist.get(res_graph.head(e))==(dist.get(res_graph.tail(e))+1)) { |
|---|
| 452 | typename MutableGraph::Edge f=F.addEdge(res_graph_to_F.get(res_graph.tail(e)), res_graph_to_F.get(res_graph.head(e))); |
|---|
| 453 | original_edge.update(); |
|---|
| 454 | original_edge.set(f, e); |
|---|
| 455 | residual_capacity.update(); |
|---|
| 456 | residual_capacity.set(f, res_graph.free(e)); |
|---|
| 457 | } |
|---|
| 458 | } |
|---|
| 459 | } |
|---|
| 460 | ++bfs; |
|---|
| 461 | } //computing distances from s in the residual graph |
|---|
| 462 | |
|---|
| 463 | bool __augment=true; |
|---|
| 464 | |
|---|
| 465 | while (__augment) { |
|---|
| 466 | __augment=false; |
|---|
| 467 | //computing blocking flow with dfs |
|---|
| 468 | typedef typename TrivGraphWrapper<MutableGraph>::NodeMap<bool> BlockingReachedMap; |
|---|
| 469 | DfsIterator5< TrivGraphWrapper<MutableGraph>/*, typename MutableGraph::OutEdgeIt*/, BlockingReachedMap > dfs(F); |
|---|
| 470 | typename MutableGraph::NodeMap<typename MutableGraph::Edge> pred(F); |
|---|
| 471 | pred.set(sF, typename MutableGraph::Edge(INVALID)); |
|---|
| 472 | //invalid iterators for sources |
|---|
| 473 | |
|---|
| 474 | typename MutableGraph::NodeMap<Number> free(F); |
|---|
| 475 | |
|---|
| 476 | dfs.pushAndSetReached(sF); |
|---|
| 477 | while (!dfs.finished()) { |
|---|
| 478 | ++dfs; |
|---|
| 479 | if (F.valid(typename MutableGraph::OutEdgeIt(dfs))) { |
|---|
| 480 | if (dfs.isBNodeNewlyReached()) { |
|---|
| 481 | typename MutableGraph::Node v=F.aNode(dfs); |
|---|
| 482 | typename MutableGraph::Node w=F.bNode(dfs); |
|---|
| 483 | pred.set(w, dfs); |
|---|
| 484 | if (F.valid(pred.get(v))) { |
|---|
| 485 | free.set(w, std::min(free.get(v), residual_capacity.get(dfs))); |
|---|
| 486 | } else { |
|---|
| 487 | free.set(w, residual_capacity.get(dfs)); |
|---|
| 488 | } |
|---|
| 489 | if (w==tF) { |
|---|
| 490 | __augment=true; |
|---|
| 491 | _augment=true; |
|---|
| 492 | break; |
|---|
| 493 | } |
|---|
| 494 | |
|---|
| 495 | } else { |
|---|
| 496 | F.erase(typename MutableGraph::OutEdgeIt(dfs)); |
|---|
| 497 | } |
|---|
| 498 | } |
|---|
| 499 | } |
|---|
| 500 | |
|---|
| 501 | if (__augment) { |
|---|
| 502 | typename MutableGraph::Node n=tF; |
|---|
| 503 | Number augment_value=free.get(tF); |
|---|
| 504 | while (F.valid(pred.get(n))) { |
|---|
| 505 | typename MutableGraph::Edge e=pred.get(n); |
|---|
| 506 | res_graph.augment(original_edge.get(e), augment_value); |
|---|
| 507 | n=F.tail(e); |
|---|
| 508 | if (residual_capacity.get(e)==augment_value) |
|---|
| 509 | F.erase(e); |
|---|
| 510 | else |
|---|
| 511 | residual_capacity.set(e, residual_capacity.get(e)-augment_value); |
|---|
| 512 | } |
|---|
| 513 | } |
|---|
| 514 | |
|---|
| 515 | } |
|---|
| 516 | |
|---|
| 517 | return _augment; |
|---|
| 518 | } |
|---|
| 519 | bool augmentOnBlockingFlow2() { |
|---|
| 520 | bool _augment=false; |
|---|
| 521 | |
|---|
| 522 | //typedef ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap> EAugGraph; |
|---|
| 523 | typedef FilterGraphWrapper< ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap> > EAugGraph; |
|---|
| 524 | typedef typename EAugGraph::OutEdgeIt EAugOutEdgeIt; |
|---|
| 525 | typedef typename EAugGraph::Edge EAugEdge; |
|---|
| 526 | |
|---|
| 527 | EAugGraph res_graph(*G, *flow, *capacity); |
|---|
| 528 | |
|---|
| 529 | //typedef typename EAugGraph::NodeMap<bool> ReachedMap; |
|---|
| 530 | BfsIterator5< |
|---|
| 531 | ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>, |
|---|
| 532 | /*typename ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>::OutEdgeIt,*/ |
|---|
| 533 | ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>::NodeMap<bool> > bfs(res_graph); |
|---|
| 534 | |
|---|
| 535 | bfs.pushAndSetReached(s); |
|---|
| 536 | |
|---|
| 537 | typename ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>:: |
|---|
| 538 | NodeMap<int>& dist=res_graph.dist; |
|---|
| 539 | |
|---|
| 540 | while ( !bfs.finished() ) { |
|---|
| 541 | typename ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>::OutEdgeIt e=bfs; |
|---|
| 542 | if (res_graph.valid(e) && bfs.isBNodeNewlyReached()) { |
|---|
| 543 | dist.set(res_graph.head(e), dist.get(res_graph.tail(e))+1); |
|---|
| 544 | } |
|---|
| 545 | ++bfs; |
|---|
| 546 | } //computing distances from s in the residual graph |
|---|
| 547 | |
|---|
| 548 | bool __augment=true; |
|---|
| 549 | |
|---|
| 550 | while (__augment) { |
|---|
| 551 | |
|---|
| 552 | __augment=false; |
|---|
| 553 | //computing blocking flow with dfs |
|---|
| 554 | typedef typename EAugGraph::NodeMap<bool> BlockingReachedMap; |
|---|
| 555 | DfsIterator5< EAugGraph/*, EAugOutEdgeIt*/, BlockingReachedMap > |
|---|
| 556 | dfs(res_graph); |
|---|
| 557 | typename EAugGraph::NodeMap<EAugEdge> pred(res_graph); |
|---|
| 558 | pred.set(s, EAugEdge(INVALID)); |
|---|
| 559 | //invalid iterators for sources |
|---|
| 560 | |
|---|
| 561 | typename EAugGraph::NodeMap<Number> free(res_graph); |
|---|
| 562 | |
|---|
| 563 | dfs.pushAndSetReached(s); |
|---|
| 564 | while (!dfs.finished()) { |
|---|
| 565 | ++dfs; |
|---|
| 566 | if (res_graph.valid(EAugOutEdgeIt(dfs))) { |
|---|
| 567 | if (dfs.isBNodeNewlyReached()) { |
|---|
| 568 | |
|---|
| 569 | typename EAugGraph::Node v=res_graph.aNode(dfs); |
|---|
| 570 | typename EAugGraph::Node w=res_graph.bNode(dfs); |
|---|
| 571 | |
|---|
| 572 | pred.set(w, EAugOutEdgeIt(dfs)); |
|---|
| 573 | if (res_graph.valid(pred.get(v))) { |
|---|
| 574 | free.set(w, std::min(free.get(v), res_graph.free(dfs))); |
|---|
| 575 | } else { |
|---|
| 576 | free.set(w, res_graph.free(dfs)); |
|---|
| 577 | } |
|---|
| 578 | |
|---|
| 579 | if (w==t) { |
|---|
| 580 | __augment=true; |
|---|
| 581 | _augment=true; |
|---|
| 582 | break; |
|---|
| 583 | } |
|---|
| 584 | } else { |
|---|
| 585 | res_graph.erase(dfs); |
|---|
| 586 | } |
|---|
| 587 | } |
|---|
| 588 | |
|---|
| 589 | } |
|---|
| 590 | |
|---|
| 591 | if (__augment) { |
|---|
| 592 | typename EAugGraph::Node n=t; |
|---|
| 593 | Number augment_value=free.get(t); |
|---|
| 594 | while (res_graph.valid(pred.get(n))) { |
|---|
| 595 | EAugEdge e=pred.get(n); |
|---|
| 596 | res_graph.augment(e, augment_value); |
|---|
| 597 | n=res_graph.tail(e); |
|---|
| 598 | if (res_graph.free(e)==0) |
|---|
| 599 | res_graph.erase(e); |
|---|
| 600 | } |
|---|
| 601 | } |
|---|
| 602 | |
|---|
| 603 | } |
|---|
| 604 | |
|---|
| 605 | return _augment; |
|---|
| 606 | } |
|---|
| 607 | void run() { |
|---|
| 608 | //int num_of_augmentations=0; |
|---|
| 609 | while (augmentOnShortestPath()) { |
|---|
| 610 | //while (augmentOnBlockingFlow<MutableGraph>()) { |
|---|
| 611 | //std::cout << ++num_of_augmentations << " "; |
|---|
| 612 | //std::cout<<std::endl; |
|---|
| 613 | } |
|---|
| 614 | } |
|---|
| 615 | template<typename MutableGraph> void run() { |
|---|
| 616 | //int num_of_augmentations=0; |
|---|
| 617 | //while (augmentOnShortestPath()) { |
|---|
| 618 | while (augmentOnBlockingFlow<MutableGraph>()) { |
|---|
| 619 | //std::cout << ++num_of_augmentations << " "; |
|---|
| 620 | //std::cout<<std::endl; |
|---|
| 621 | } |
|---|
| 622 | } |
|---|
| 623 | Number flowValue() { |
|---|
| 624 | Number a=0; |
|---|
| 625 | OutEdgeIt e; |
|---|
| 626 | for(G->/*getF*/first(e, s); G->valid(e); G->next(e)) { |
|---|
| 627 | a+=flow->get(e); |
|---|
| 628 | } |
|---|
| 629 | return a; |
|---|
| 630 | } |
|---|
| 631 | }; |
|---|
| 632 | |
|---|
| 633 | |
|---|
| 634 | template <typename Graph, typename Number, typename FlowMap, typename CapacityMap> |
|---|
| 635 | class MaxMatching { |
|---|
| 636 | public: |
|---|
| 637 | typedef typename Graph::Node Node; |
|---|
| 638 | typedef typename Graph::NodeIt NodeIt; |
|---|
| 639 | typedef typename Graph::Edge Edge; |
|---|
| 640 | typedef typename Graph::EdgeIt EdgeIt; |
|---|
| 641 | typedef typename Graph::OutEdgeIt OutEdgeIt; |
|---|
| 642 | typedef typename Graph::InEdgeIt InEdgeIt; |
|---|
| 643 | |
|---|
| 644 | typedef typename Graph::NodeMap<bool> SMap; |
|---|
| 645 | typedef typename Graph::NodeMap<bool> TMap; |
|---|
| 646 | private: |
|---|
| 647 | const Graph* G; |
|---|
| 648 | SMap* S; |
|---|
| 649 | TMap* T; |
|---|
| 650 | //Node s; |
|---|
| 651 | //Node t; |
|---|
| 652 | FlowMap* flow; |
|---|
| 653 | const CapacityMap* capacity; |
|---|
| 654 | typedef ResGraphWrapper<Graph, Number, FlowMap, CapacityMap > AugGraph; |
|---|
| 655 | typedef typename AugGraph::OutEdgeIt AugOutEdgeIt; |
|---|
| 656 | typedef typename AugGraph::Edge AugEdge; |
|---|
| 657 | typename Graph::NodeMap<int> used; //0 |
|---|
| 658 | |
|---|
| 659 | public: |
|---|
| 660 | MaxMatching(const Graph& _G, SMap& _S, TMap& _T, FlowMap& _flow, const CapacityMap& _capacity) : |
|---|
| 661 | G(&_G), S(&_S), T(&_T), flow(&_flow), capacity(&_capacity), used(_G) { } |
|---|
| 662 | bool augmentOnShortestPath() { |
|---|
| 663 | AugGraph res_graph(*G, *flow, *capacity); |
|---|
| 664 | bool _augment=false; |
|---|
| 665 | |
|---|
| 666 | typedef typename AugGraph::NodeMap<bool> ReachedMap; |
|---|
| 667 | BfsIterator5< AugGraph, /*AugOutEdgeIt,*/ ReachedMap > res_bfs(res_graph); |
|---|
| 668 | typename AugGraph::NodeMap<AugEdge> pred(res_graph); |
|---|
| 669 | for(NodeIt s=G->template first<NodeIt>(); G->valid(s); G->next(s)) { |
|---|
| 670 | if ((S->get(s)) && (used.get(s)<1) ) { |
|---|
| 671 | //Number u=0; |
|---|
| 672 | //for(OutEdgeIt e=G->template first<OutEdgeIt>(s); G->valid(e); G->next(e)) |
|---|
| 673 | //u+=flow->get(e); |
|---|
| 674 | //if (u<1) { |
|---|
| 675 | res_bfs.pushAndSetReached(s); |
|---|
| 676 | pred.set(s, AugEdge(INVALID)); |
|---|
| 677 | //} |
|---|
| 678 | } |
|---|
| 679 | } |
|---|
| 680 | |
|---|
| 681 | typename AugGraph::NodeMap<Number> free(res_graph); |
|---|
| 682 | |
|---|
| 683 | Node n; |
|---|
| 684 | //searching for augmenting path |
|---|
| 685 | while ( !res_bfs.finished() ) { |
|---|
| 686 | AugOutEdgeIt e=res_bfs; |
|---|
| 687 | if (res_graph.valid(e) && res_bfs.isBNodeNewlyReached()) { |
|---|
| 688 | Node v=res_graph.tail(e); |
|---|
| 689 | Node w=res_graph.head(e); |
|---|
| 690 | pred.set(w, e); |
|---|
| 691 | if (res_graph.valid(pred.get(v))) { |
|---|
| 692 | free.set(w, std::min(free.get(v), res_graph.free(e))); |
|---|
| 693 | } else { |
|---|
| 694 | free.set(w, res_graph.free(e)); |
|---|
| 695 | } |
|---|
| 696 | n=res_graph.head(e); |
|---|
| 697 | if (T->get(n) && (used.get(n)<1) ) { |
|---|
| 698 | //Number u=0; |
|---|
| 699 | //for(InEdgeIt f=G->template first<InEdgeIt>(n); G->valid(f); G->next(f)) |
|---|
| 700 | //u+=flow->get(f); |
|---|
| 701 | //if (u<1) { |
|---|
| 702 | _augment=true; |
|---|
| 703 | break; |
|---|
| 704 | //} |
|---|
| 705 | } |
|---|
| 706 | } |
|---|
| 707 | |
|---|
| 708 | ++res_bfs; |
|---|
| 709 | } //end of searching augmenting path |
|---|
| 710 | |
|---|
| 711 | if (_augment) { |
|---|
| 712 | //Node n=t; |
|---|
| 713 | used.set(n, 1); //mind2 vegen jav |
|---|
| 714 | Number augment_value=free.get(n); |
|---|
| 715 | while (res_graph.valid(pred.get(n))) { |
|---|
| 716 | AugEdge e=pred.get(n); |
|---|
| 717 | res_graph.augment(e, augment_value); |
|---|
| 718 | n=res_graph.tail(e); |
|---|
| 719 | } |
|---|
| 720 | used.set(n, 1); //mind2 vegen jav |
|---|
| 721 | } |
|---|
| 722 | |
|---|
| 723 | return _augment; |
|---|
| 724 | } |
|---|
| 725 | |
|---|
| 726 | // template<typename MutableGraph> bool augmentOnBlockingFlow() { |
|---|
| 727 | // bool _augment=false; |
|---|
| 728 | |
|---|
| 729 | // AugGraph res_graph(*G, *flow, *capacity); |
|---|
| 730 | |
|---|
| 731 | // typedef typename AugGraph::NodeMap<bool> ReachedMap; |
|---|
| 732 | // BfsIterator4< AugGraph, AugOutEdgeIt, ReachedMap > bfs(res_graph); |
|---|
| 733 | |
|---|
| 734 | |
|---|
| 735 | |
|---|
| 736 | |
|---|
| 737 | |
|---|
| 738 | // //typename AugGraph::NodeMap<AugEdge> pred(res_graph); |
|---|
| 739 | // for(NodeIt s=G->template first<NodeIt>(); G->valid(s); G->next(s)) { |
|---|
| 740 | // if (S->get(s)) { |
|---|
| 741 | // Number u=0; |
|---|
| 742 | // for(OutEdgeIt e=G->template first<OutEdgeIt>(s); G->valid(e); G->next(e)) |
|---|
| 743 | // u+=flow->get(e); |
|---|
| 744 | // if (u<1) { |
|---|
| 745 | // res_bfs.pushAndSetReached(s); |
|---|
| 746 | // //pred.set(s, AugEdge(INVALID)); |
|---|
| 747 | // } |
|---|
| 748 | // } |
|---|
| 749 | // } |
|---|
| 750 | |
|---|
| 751 | |
|---|
| 752 | |
|---|
| 753 | |
|---|
| 754 | // //bfs.pushAndSetReached(s); |
|---|
| 755 | // typename AugGraph::NodeMap<int> dist(res_graph); //filled up with 0's |
|---|
| 756 | // while ( !bfs.finished() ) { |
|---|
| 757 | // AugOutEdgeIt e=bfs; |
|---|
| 758 | // if (res_graph.valid(e) && bfs.isBNodeNewlyReached()) { |
|---|
| 759 | // dist.set(res_graph.head(e), dist.get(res_graph.tail(e))+1); |
|---|
| 760 | // } |
|---|
| 761 | |
|---|
| 762 | // ++bfs; |
|---|
| 763 | // } //computing distances from s in the residual graph |
|---|
| 764 | |
|---|
| 765 | // MutableGraph F; |
|---|
| 766 | // typename AugGraph::NodeMap<typename MutableGraph::Node> |
|---|
| 767 | // res_graph_to_F(res_graph); |
|---|
| 768 | // for(typename AugGraph::NodeIt n=res_graph.template first<typename AugGraph::NodeIt>(); res_graph.valid(n); res_graph.next(n)) { |
|---|
| 769 | // res_graph_to_F.set(n, F.addNode()); |
|---|
| 770 | // } |
|---|
| 771 | |
|---|
| 772 | // typename MutableGraph::Node sF=res_graph_to_F.get(s); |
|---|
| 773 | // typename MutableGraph::Node tF=res_graph_to_F.get(t); |
|---|
| 774 | |
|---|
| 775 | // typename MutableGraph::EdgeMap<AugEdge> original_edge(F); |
|---|
| 776 | // typename MutableGraph::EdgeMap<Number> residual_capacity(F); |
|---|
| 777 | |
|---|
| 778 | // //Making F to the graph containing the edges of the residual graph |
|---|
| 779 | // //which are in some shortest paths |
|---|
| 780 | // for(typename AugGraph::EdgeIt e=res_graph.template first<typename AugGraph::EdgeIt>(); res_graph.valid(e); res_graph.next(e)) { |
|---|
| 781 | // if (dist.get(res_graph.head(e))==dist.get(res_graph.tail(e))+1) { |
|---|
| 782 | // typename MutableGraph::Edge f=F.addEdge(res_graph_to_F.get(res_graph.tail(e)), res_graph_to_F.get(res_graph.head(e))); |
|---|
| 783 | // original_edge.update(); |
|---|
| 784 | // original_edge.set(f, e); |
|---|
| 785 | // residual_capacity.update(); |
|---|
| 786 | // residual_capacity.set(f, res_graph.free(e)); |
|---|
| 787 | // } |
|---|
| 788 | // } |
|---|
| 789 | |
|---|
| 790 | // bool __augment=true; |
|---|
| 791 | |
|---|
| 792 | // while (__augment) { |
|---|
| 793 | // __augment=false; |
|---|
| 794 | // //computing blocking flow with dfs |
|---|
| 795 | // typedef typename MutableGraph::NodeMap<bool> BlockingReachedMap; |
|---|
| 796 | // DfsIterator4< MutableGraph, typename MutableGraph::OutEdgeIt, BlockingReachedMap > dfs(F); |
|---|
| 797 | // typename MutableGraph::NodeMap<typename MutableGraph::Edge> pred(F); |
|---|
| 798 | // pred.set(sF, typename MutableGraph::Edge(INVALID)); |
|---|
| 799 | // //invalid iterators for sources |
|---|
| 800 | |
|---|
| 801 | // typename MutableGraph::NodeMap<Number> free(F); |
|---|
| 802 | |
|---|
| 803 | // dfs.pushAndSetReached(sF); |
|---|
| 804 | // while (!dfs.finished()) { |
|---|
| 805 | // ++dfs; |
|---|
| 806 | // if (F.valid(typename MutableGraph::OutEdgeIt(dfs))) { |
|---|
| 807 | // if (dfs.isBNodeNewlyReached()) { |
|---|
| 808 | // typename MutableGraph::Node v=F.aNode(dfs); |
|---|
| 809 | // typename MutableGraph::Node w=F.bNode(dfs); |
|---|
| 810 | // pred.set(w, dfs); |
|---|
| 811 | // if (F.valid(pred.get(v))) { |
|---|
| 812 | // free.set(w, std::min(free.get(v), residual_capacity.get(dfs))); |
|---|
| 813 | // } else { |
|---|
| 814 | // free.set(w, residual_capacity.get(dfs)); |
|---|
| 815 | // } |
|---|
| 816 | // if (w==tF) { |
|---|
| 817 | // __augment=true; |
|---|
| 818 | // _augment=true; |
|---|
| 819 | // break; |
|---|
| 820 | // } |
|---|
| 821 | |
|---|
| 822 | // } else { |
|---|
| 823 | // F.erase(typename MutableGraph::OutEdgeIt(dfs)); |
|---|
| 824 | // } |
|---|
| 825 | // } |
|---|
| 826 | // } |
|---|
| 827 | |
|---|
| 828 | // if (__augment) { |
|---|
| 829 | // typename MutableGraph::Node n=tF; |
|---|
| 830 | // Number augment_value=free.get(tF); |
|---|
| 831 | // while (F.valid(pred.get(n))) { |
|---|
| 832 | // typename MutableGraph::Edge e=pred.get(n); |
|---|
| 833 | // res_graph.augment(original_edge.get(e), augment_value); |
|---|
| 834 | // n=F.tail(e); |
|---|
| 835 | // if (residual_capacity.get(e)==augment_value) |
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| 836 | // F.erase(e); |
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| 837 | // else |
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| 838 | // residual_capacity.set(e, residual_capacity.get(e)-augment_value); |
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| 839 | // } |
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| 840 | // } |
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| 841 | |
|---|
| 842 | // } |
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| 843 | |
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| 844 | // return _augment; |
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| 845 | // } |
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| 846 | bool augmentOnBlockingFlow2() { |
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| 847 | bool _augment=false; |
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| 848 | |
|---|
| 849 | //typedef ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap> EAugGraph; |
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| 850 | typedef FilterGraphWrapper< ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap> > EAugGraph; |
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| 851 | typedef typename EAugGraph::OutEdgeIt EAugOutEdgeIt; |
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| 852 | typedef typename EAugGraph::Edge EAugEdge; |
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| 853 | |
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| 854 | EAugGraph res_graph(*G, *flow, *capacity); |
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| 855 | |
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| 856 | //typedef typename EAugGraph::NodeMap<bool> ReachedMap; |
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| 857 | BfsIterator5< |
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| 858 | ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>, |
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| 859 | /*typename ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>::OutEdgeIt,*/ |
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| 860 | ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>::NodeMap<bool> > bfs(res_graph); |
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| 861 | |
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| 862 | |
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| 863 | //typename AugGraph::NodeMap<AugEdge> pred(res_graph); |
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| 864 | for(NodeIt s=G->template first<NodeIt>(); G->valid(s); G->next(s)) { |
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| 865 | if (S->get(s)) { |
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| 866 | Number u=0; |
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| 867 | for(OutEdgeIt e=G->template first<OutEdgeIt>(s); G->valid(e); G->next(e)) |
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| 868 | u+=flow->get(e); |
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| 869 | if (u<1) { |
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| 870 | bfs.pushAndSetReached(s); |
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| 871 | //pred.set(s, AugEdge(INVALID)); |
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| 872 | } |
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| 873 | } |
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| 874 | } |
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| 875 | |
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| 876 | |
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| 877 | //bfs.pushAndSetReached(s); |
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| 878 | |
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| 879 | typename ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>:: |
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| 880 | NodeMap<int>& dist=res_graph.dist; |
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| 881 | |
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| 882 | while ( !bfs.finished() ) { |
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| 883 | typename ErasingResGraphWrapper<Graph, Number, FlowMap, CapacityMap>::OutEdgeIt e=bfs; |
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| 884 | if (res_graph.valid(e) && bfs.isBNodeNewlyReached()) { |
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| 885 | dist.set(res_graph.head(e), dist.get(res_graph.tail(e))+1); |
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| 886 | } |
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| 887 | ++bfs; |
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| 888 | } //computing distances from s in the residual graph |
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| 889 | |
|---|
| 890 | bool __augment=true; |
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| 891 | |
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| 892 | while (__augment) { |
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| 893 | |
|---|
| 894 | __augment=false; |
|---|
| 895 | //computing blocking flow with dfs |
|---|
| 896 | typedef typename EAugGraph::NodeMap<bool> BlockingReachedMap; |
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| 897 | DfsIterator5< EAugGraph/*, EAugOutEdgeIt*/, BlockingReachedMap > |
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| 898 | dfs(res_graph); |
|---|
| 899 | typename EAugGraph::NodeMap<EAugEdge> pred(res_graph, INVALID); |
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| 900 | //pred.set(s, EAugEdge(INVALID)); |
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| 901 | //invalid iterators for sources |
|---|
| 902 | |
|---|
| 903 | typename EAugGraph::NodeMap<Number> free(res_graph); |
|---|
| 904 | |
|---|
| 905 | |
|---|
| 906 | //typename AugGraph::NodeMap<AugEdge> pred(res_graph); |
|---|
| 907 | for(NodeIt s=G->template first<NodeIt>(); G->valid(s); G->next(s)) { |
|---|
| 908 | if (S->get(s)) { |
|---|
| 909 | Number u=0; |
|---|
| 910 | for(OutEdgeIt e=G->template first<OutEdgeIt>(s); G->valid(e); G->next(e)) |
|---|
| 911 | u+=flow->get(e); |
|---|
| 912 | if (u<1) { |
|---|
| 913 | dfs.pushAndSetReached(s); |
|---|
| 914 | //pred.set(s, AugEdge(INVALID)); |
|---|
| 915 | } |
|---|
| 916 | } |
|---|
| 917 | } |
|---|
| 918 | |
|---|
| 919 | |
|---|
| 920 | |
|---|
| 921 | //dfs.pushAndSetReached(s); |
|---|
| 922 | typename EAugGraph::Node n; |
|---|
| 923 | while (!dfs.finished()) { |
|---|
| 924 | ++dfs; |
|---|
| 925 | if (res_graph.valid(EAugOutEdgeIt(dfs))) { |
|---|
| 926 | if (dfs.isBNodeNewlyReached()) { |
|---|
| 927 | |
|---|
| 928 | typename EAugGraph::Node v=res_graph.aNode(dfs); |
|---|
| 929 | typename EAugGraph::Node w=res_graph.bNode(dfs); |
|---|
| 930 | |
|---|
| 931 | pred.set(w, EAugOutEdgeIt(dfs)); |
|---|
| 932 | if (res_graph.valid(pred.get(v))) { |
|---|
| 933 | free.set(w, std::min(free.get(v), res_graph.free(dfs))); |
|---|
| 934 | } else { |
|---|
| 935 | free.set(w, res_graph.free(dfs)); |
|---|
| 936 | } |
|---|
| 937 | |
|---|
| 938 | n=w; |
|---|
| 939 | if (T->get(w)) { |
|---|
| 940 | Number u=0; |
|---|
| 941 | for(InEdgeIt f=G->template first<InEdgeIt>(n); G->valid(f); G->next(f)) |
|---|
| 942 | u+=flow->get(f); |
|---|
| 943 | if (u<1) { |
|---|
| 944 | __augment=true; |
|---|
| 945 | _augment=true; |
|---|
| 946 | break; |
|---|
| 947 | } |
|---|
| 948 | } |
|---|
| 949 | } else { |
|---|
| 950 | res_graph.erase(dfs); |
|---|
| 951 | } |
|---|
| 952 | } |
|---|
| 953 | |
|---|
| 954 | } |
|---|
| 955 | |
|---|
| 956 | if (__augment) { |
|---|
| 957 | // typename EAugGraph::Node n=t; |
|---|
| 958 | Number augment_value=free.get(n); |
|---|
| 959 | while (res_graph.valid(pred.get(n))) { |
|---|
| 960 | EAugEdge e=pred.get(n); |
|---|
| 961 | res_graph.augment(e, augment_value); |
|---|
| 962 | n=res_graph.tail(e); |
|---|
| 963 | if (res_graph.free(e)==0) |
|---|
| 964 | res_graph.erase(e); |
|---|
| 965 | } |
|---|
| 966 | } |
|---|
| 967 | |
|---|
| 968 | } |
|---|
| 969 | |
|---|
| 970 | return _augment; |
|---|
| 971 | } |
|---|
| 972 | void run() { |
|---|
| 973 | //int num_of_augmentations=0; |
|---|
| 974 | while (augmentOnShortestPath()) { |
|---|
| 975 | //while (augmentOnBlockingFlow<MutableGraph>()) { |
|---|
| 976 | //std::cout << ++num_of_augmentations << " "; |
|---|
| 977 | //std::cout<<std::endl; |
|---|
| 978 | } |
|---|
| 979 | } |
|---|
| 980 | // template<typename MutableGraph> void run() { |
|---|
| 981 | // //int num_of_augmentations=0; |
|---|
| 982 | // //while (augmentOnShortestPath()) { |
|---|
| 983 | // while (augmentOnBlockingFlow<MutableGraph>()) { |
|---|
| 984 | // //std::cout << ++num_of_augmentations << " "; |
|---|
| 985 | // //std::cout<<std::endl; |
|---|
| 986 | // } |
|---|
| 987 | // } |
|---|
| 988 | Number flowValue() { |
|---|
| 989 | Number a=0; |
|---|
| 990 | EdgeIt e; |
|---|
| 991 | for(G->/*getF*/first(e); G->valid(e); G->next(e)) { |
|---|
| 992 | a+=flow->get(e); |
|---|
| 993 | } |
|---|
| 994 | return a; |
|---|
| 995 | } |
|---|
| 996 | }; |
|---|
| 997 | |
|---|
| 998 | |
|---|
| 999 | |
|---|
| 1000 | |
|---|
| 1001 | |
|---|
| 1002 | |
|---|
| 1003 | // template <typename Graph, typename Number, typename FlowMap, typename CapacityMap> |
|---|
| 1004 | // class MaxFlow2 { |
|---|
| 1005 | // public: |
|---|
| 1006 | // typedef typename Graph::Node Node; |
|---|
| 1007 | // typedef typename Graph::Edge Edge; |
|---|
| 1008 | // typedef typename Graph::EdgeIt EdgeIt; |
|---|
| 1009 | // typedef typename Graph::OutEdgeIt OutEdgeIt; |
|---|
| 1010 | // typedef typename Graph::InEdgeIt InEdgeIt; |
|---|
| 1011 | // private: |
|---|
| 1012 | // const Graph& G; |
|---|
| 1013 | // std::list<Node>& S; |
|---|
| 1014 | // std::list<Node>& T; |
|---|
| 1015 | // FlowMap& flow; |
|---|
| 1016 | // const CapacityMap& capacity; |
|---|
| 1017 | // typedef ResGraphWrapper<Graph, Number, FlowMap, CapacityMap > AugGraph; |
|---|
| 1018 | // typedef typename AugGraph::OutEdgeIt AugOutEdgeIt; |
|---|
| 1019 | // typedef typename AugGraph::Edge AugEdge; |
|---|
| 1020 | // typename Graph::NodeMap<bool> SMap; |
|---|
| 1021 | // typename Graph::NodeMap<bool> TMap; |
|---|
| 1022 | // public: |
|---|
| 1023 | // MaxFlow2(const Graph& _G, std::list<Node>& _S, std::list<Node>& _T, FlowMap& _flow, const CapacityMap& _capacity) : G(_G), S(_S), T(_T), flow(_flow), capacity(_capacity), SMap(_G), TMap(_G) { |
|---|
| 1024 | // for(typename std::list<Node>::const_iterator i=S.begin(); |
|---|
| 1025 | // i!=S.end(); ++i) { |
|---|
| 1026 | // SMap.set(*i, true); |
|---|
| 1027 | // } |
|---|
| 1028 | // for (typename std::list<Node>::const_iterator i=T.begin(); |
|---|
| 1029 | // i!=T.end(); ++i) { |
|---|
| 1030 | // TMap.set(*i, true); |
|---|
| 1031 | // } |
|---|
| 1032 | // } |
|---|
| 1033 | // bool augment() { |
|---|
| 1034 | // AugGraph res_graph(G, flow, capacity); |
|---|
| 1035 | // bool _augment=false; |
|---|
| 1036 | // Node reached_t_node; |
|---|
| 1037 | |
|---|
| 1038 | // typedef typename AugGraph::NodeMap<bool> ReachedMap; |
|---|
| 1039 | // BfsIterator4< AugGraph, AugOutEdgeIt, ReachedMap > res_bfs(res_graph); |
|---|
| 1040 | // for(typename std::list<Node>::const_iterator i=S.begin(); |
|---|
| 1041 | // i!=S.end(); ++i) { |
|---|
| 1042 | // res_bfs.pushAndSetReached(*i); |
|---|
| 1043 | // } |
|---|
| 1044 | // //res_bfs.pushAndSetReached(s); |
|---|
| 1045 | |
|---|
| 1046 | // typename AugGraph::NodeMap<AugEdge> pred(res_graph); |
|---|
| 1047 | // //filled up with invalid iterators |
|---|
| 1048 | |
|---|
| 1049 | // typename AugGraph::NodeMap<Number> free(res_graph); |
|---|
| 1050 | |
|---|
| 1051 | // //searching for augmenting path |
|---|
| 1052 | // while ( !res_bfs.finished() ) { |
|---|
| 1053 | // AugOutEdgeIt e=/*AugOutEdgeIt*/(res_bfs); |
|---|
| 1054 | // if (e.valid() && res_bfs.isBNodeNewlyReached()) { |
|---|
| 1055 | // Node v=res_graph.tail(e); |
|---|
| 1056 | // Node w=res_graph.head(e); |
|---|
| 1057 | // pred.set(w, e); |
|---|
| 1058 | // if (pred.get(v).valid()) { |
|---|
| 1059 | // free.set(w, std::min(free.get(v), e.free())); |
|---|
| 1060 | // } else { |
|---|
| 1061 | // free.set(w, e.free()); |
|---|
| 1062 | // } |
|---|
| 1063 | // if (TMap.get(res_graph.head(e))) { |
|---|
| 1064 | // _augment=true; |
|---|
| 1065 | // reached_t_node=res_graph.head(e); |
|---|
| 1066 | // break; |
|---|
| 1067 | // } |
|---|
| 1068 | // } |
|---|
| 1069 | |
|---|
| 1070 | // ++res_bfs; |
|---|
| 1071 | // } //end of searching augmenting path |
|---|
| 1072 | |
|---|
| 1073 | // if (_augment) { |
|---|
| 1074 | // Node n=reached_t_node; |
|---|
| 1075 | // Number augment_value=free.get(reached_t_node); |
|---|
| 1076 | // while (pred.get(n).valid()) { |
|---|
| 1077 | // AugEdge e=pred.get(n); |
|---|
| 1078 | // e.augment(augment_value); |
|---|
| 1079 | // n=res_graph.tail(e); |
|---|
| 1080 | // } |
|---|
| 1081 | // } |
|---|
| 1082 | |
|---|
| 1083 | // return _augment; |
|---|
| 1084 | // } |
|---|
| 1085 | // void run() { |
|---|
| 1086 | // while (augment()) { } |
|---|
| 1087 | // } |
|---|
| 1088 | // Number flowValue() { |
|---|
| 1089 | // Number a=0; |
|---|
| 1090 | // for(typename std::list<Node>::const_iterator i=S.begin(); |
|---|
| 1091 | // i!=S.end(); ++i) { |
|---|
| 1092 | // for(OutEdgeIt e=G.template first<OutEdgeIt>(*i); e.valid(); ++e) { |
|---|
| 1093 | // a+=flow.get(e); |
|---|
| 1094 | // } |
|---|
| 1095 | // for(InEdgeIt e=G.template first<InEdgeIt>(*i); e.valid(); ++e) { |
|---|
| 1096 | // a-=flow.get(e); |
|---|
| 1097 | // } |
|---|
| 1098 | // } |
|---|
| 1099 | // return a; |
|---|
| 1100 | // } |
|---|
| 1101 | // }; |
|---|
| 1102 | |
|---|
| 1103 | |
|---|
| 1104 | |
|---|
| 1105 | } // namespace hugo |
|---|
| 1106 | |
|---|
| 1107 | #endif //EDMONDS_KARP_H |
|---|