[370] | 1 | // -*- C++ -*- |
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| 2 | |
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| 3 | //run gyorsan tudna adni a minmincutot a 2 fazis elejen , ne vegyuk be konstruktorba egy cutmapet? |
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| 4 | //constzero jo igy? |
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| 5 | |
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| 6 | //majd marci megmondja betegyem-e bfs-t meg resgraphot |
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| 7 | |
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| 8 | /* |
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| 9 | Heuristics: |
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| 10 | 2 phase |
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| 11 | gap |
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| 12 | list 'level_list' on the nodes on level i implemented by hand |
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| 13 | stack 'active' on the active nodes on level i implemented by hand |
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| 14 | runs heuristic 'highest label' for H1*n relabels |
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| 15 | runs heuristic 'bound decrease' for H0*n relabels, starts with 'highest label' |
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| 16 | |
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| 17 | Parameters H0 and H1 are initialized to 20 and 10. |
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| 18 | |
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| 19 | Constructors: |
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| 20 | |
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| 21 | Preflow(Graph, Node, Node, CapMap, FlowMap, bool) : bool must be false if |
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| 22 | FlowMap is not constant zero, and should be true if it is |
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| 23 | |
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| 24 | Members: |
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| 25 | |
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| 26 | void run() |
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| 27 | |
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| 28 | T flowValue() : returns the value of a maximum flow |
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| 29 | |
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| 30 | void minMinCut(CutMap& M) : sets M to the characteristic vector of the |
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| 31 | minimum min cut. M should be a map of bools initialized to false. |
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| 32 | |
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| 33 | void maxMinCut(CutMap& M) : sets M to the characteristic vector of the |
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| 34 | maximum min cut. M should be a map of bools initialized to false. |
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| 35 | |
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| 36 | void minCut(CutMap& M) : sets M to the characteristic vector of |
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| 37 | a min cut. M should be a map of bools initialized to false. |
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| 38 | |
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| 39 | FIXME reset |
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| 40 | |
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| 41 | */ |
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| 42 | |
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[376] | 43 | #ifndef HUGO_PREFLOW_PROBA_H |
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| 44 | #define HUGO_PREFLOW_PROBA_H |
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[370] | 45 | |
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| 46 | #define H0 20 |
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| 47 | #define H1 1 |
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| 48 | |
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| 49 | #include <vector> |
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| 50 | #include <queue> |
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| 51 | #include<graph_wrapper.h> |
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| 52 | |
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| 53 | namespace hugo { |
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| 54 | |
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| 55 | template <typename Graph, typename T, |
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| 56 | typename CapMap=typename Graph::EdgeMap<T>, |
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| 57 | typename FlowMap=typename Graph::EdgeMap<T> > |
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[376] | 58 | class PreflowProba { |
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[370] | 59 | |
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| 60 | typedef typename Graph::Node Node; |
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| 61 | typedef typename Graph::Edge Edge; |
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| 62 | typedef typename Graph::NodeIt NodeIt; |
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| 63 | typedef typename Graph::OutEdgeIt OutEdgeIt; |
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| 64 | typedef typename Graph::InEdgeIt InEdgeIt; |
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| 65 | |
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| 66 | const Graph& G; |
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| 67 | Node s; |
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| 68 | Node t; |
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| 69 | const CapMap& capacity; |
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| 70 | FlowMap& flow; |
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| 71 | T value; |
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| 72 | bool constzero; |
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[374] | 73 | bool res; |
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[370] | 74 | |
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| 75 | typedef ResGraphWrapper<const Graph, T, CapMap, FlowMap> ResGW; |
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| 76 | typedef typename ResGW::OutEdgeIt ResOutEdgeIt; |
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| 77 | typedef typename ResGW::InEdgeIt ResInEdgeIt; |
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| 78 | typedef typename ResGW::Edge ResEdge; |
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| 79 | |
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| 80 | public: |
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[376] | 81 | PreflowProba(Graph& _G, Node _s, Node _t, CapMap& _capacity, |
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[374] | 82 | FlowMap& _flow, bool _constzero, bool _res ) : |
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| 83 | G(_G), s(_s), t(_t), capacity(_capacity), flow(_flow), constzero(_constzero), res(_res) {} |
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[370] | 84 | |
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| 85 | |
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| 86 | void run() { |
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| 87 | |
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| 88 | ResGW res_graph(G, capacity, flow); |
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| 89 | |
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| 90 | value=0; //for the subsequent runs |
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| 91 | |
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| 92 | bool phase=0; //phase 0 is the 1st phase, phase 1 is the 2nd |
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| 93 | int n=G.nodeNum(); |
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| 94 | int heur0=(int)(H0*n); //time while running 'bound decrease' |
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| 95 | int heur1=(int)(H1*n); //time while running 'highest label' |
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| 96 | int heur=heur1; //starting time interval (#of relabels) |
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| 97 | bool what_heur=1; |
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| 98 | /* |
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| 99 | what_heur is 0 in case 'bound decrease' |
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| 100 | and 1 in case 'highest label' |
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| 101 | */ |
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| 102 | bool end=false; |
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| 103 | /* |
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| 104 | Needed for 'bound decrease', 'true' |
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| 105 | means no active nodes are above bound b. |
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| 106 | */ |
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| 107 | int relabel=0; |
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| 108 | int k=n-2; //bound on the highest level under n containing a node |
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| 109 | int b=k; //bound on the highest level under n of an active node |
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| 110 | |
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| 111 | typename Graph::NodeMap<int> level(G,n); |
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| 112 | typename Graph::NodeMap<T> excess(G); |
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| 113 | |
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| 114 | std::vector<Node> active(n-1,INVALID); |
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| 115 | typename Graph::NodeMap<Node> next(G,INVALID); |
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| 116 | //Stack of the active nodes in level i < n. |
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| 117 | //We use it in both phases. |
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| 118 | |
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| 119 | typename Graph::NodeMap<Node> left(G,INVALID); |
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| 120 | typename Graph::NodeMap<Node> right(G,INVALID); |
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| 121 | std::vector<Node> level_list(n,INVALID); |
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| 122 | /* |
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| 123 | List of the nodes in level i<n. |
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| 124 | */ |
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| 125 | |
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| 126 | |
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| 127 | if ( constzero ) { |
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| 128 | |
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| 129 | /*Reverse_bfs from t, to find the starting level.*/ |
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| 130 | level.set(t,0); |
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| 131 | std::queue<Node> bfs_queue; |
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| 132 | bfs_queue.push(t); |
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| 133 | |
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| 134 | while (!bfs_queue.empty()) { |
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| 135 | |
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| 136 | Node v=bfs_queue.front(); |
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| 137 | bfs_queue.pop(); |
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| 138 | int l=level[v]+1; |
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| 139 | |
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| 140 | InEdgeIt e; |
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| 141 | for(G.first(e,v); G.valid(e); G.next(e)) { |
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| 142 | Node w=G.tail(e); |
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| 143 | if ( level[w] == n && w != s ) { |
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| 144 | bfs_queue.push(w); |
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| 145 | Node first=level_list[l]; |
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| 146 | if ( G.valid(first) ) left.set(first,w); |
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| 147 | right.set(w,first); |
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| 148 | level_list[l]=w; |
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| 149 | level.set(w, l); |
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| 150 | } |
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| 151 | } |
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| 152 | } |
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| 153 | |
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| 154 | //the starting flow |
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| 155 | OutEdgeIt e; |
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| 156 | for(G.first(e,s); G.valid(e); G.next(e)) |
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| 157 | { |
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| 158 | T c=capacity[e]; |
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| 159 | if ( c == 0 ) continue; |
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| 160 | Node w=G.head(e); |
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| 161 | if ( level[w] < n ) { |
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| 162 | if ( excess[w] == 0 && w!=t ) { |
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| 163 | next.set(w,active[level[w]]); |
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| 164 | active[level[w]]=w; |
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| 165 | } |
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| 166 | flow.set(e, c); |
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| 167 | excess.set(w, excess[w]+c); |
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| 168 | } |
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| 169 | } |
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| 170 | } |
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| 171 | else |
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| 172 | { |
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| 173 | |
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| 174 | /* |
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| 175 | Reverse_bfs from t in the residual graph, |
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| 176 | to find the starting level. |
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| 177 | */ |
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| 178 | level.set(t,0); |
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| 179 | std::queue<Node> bfs_queue; |
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| 180 | bfs_queue.push(t); |
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| 181 | |
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| 182 | while (!bfs_queue.empty()) { |
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| 183 | |
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| 184 | Node v=bfs_queue.front(); |
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| 185 | bfs_queue.pop(); |
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| 186 | int l=level[v]+1; |
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| 187 | |
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| 188 | InEdgeIt e; |
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| 189 | for(G.first(e,v); G.valid(e); G.next(e)) { |
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| 190 | if ( capacity[e] == flow[e] ) continue; |
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| 191 | Node w=G.tail(e); |
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| 192 | if ( level[w] == n && w != s ) { |
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| 193 | bfs_queue.push(w); |
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| 194 | Node first=level_list[l]; |
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| 195 | if ( G.valid(first) ) left.set(first,w); |
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| 196 | right.set(w,first); |
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| 197 | level_list[l]=w; |
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| 198 | level.set(w, l); |
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| 199 | } |
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| 200 | } |
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| 201 | |
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| 202 | OutEdgeIt f; |
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| 203 | for(G.first(f,v); G.valid(f); G.next(f)) { |
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| 204 | if ( 0 == flow[f] ) continue; |
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| 205 | Node w=G.head(f); |
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| 206 | if ( level[w] == n && w != s ) { |
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| 207 | bfs_queue.push(w); |
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| 208 | Node first=level_list[l]; |
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| 209 | if ( G.valid(first) ) left.set(first,w); |
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| 210 | right.set(w,first); |
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| 211 | level_list[l]=w; |
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| 212 | level.set(w, l); |
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| 213 | } |
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| 214 | } |
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| 215 | } |
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| 216 | |
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| 217 | |
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| 218 | /* |
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| 219 | Counting the excess |
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| 220 | */ |
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| 221 | NodeIt v; |
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| 222 | for(G.first(v); G.valid(v); G.next(v)) { |
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| 223 | T exc=0; |
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| 224 | |
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| 225 | InEdgeIt e; |
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| 226 | for(G.first(e,v); G.valid(e); G.next(e)) exc+=flow[e]; |
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| 227 | OutEdgeIt f; |
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| 228 | for(G.first(f,v); G.valid(f); G.next(f)) exc-=flow[e]; |
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| 229 | |
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| 230 | excess.set(v,exc); |
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| 231 | |
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| 232 | //putting the active nodes into the stack |
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| 233 | int lev=level[v]; |
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| 234 | if ( exc > 0 && lev < n ) { |
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| 235 | next.set(v,active[lev]); |
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| 236 | active[lev]=v; |
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| 237 | } |
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| 238 | } |
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| 239 | |
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| 240 | |
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| 241 | //the starting flow |
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| 242 | OutEdgeIt e; |
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| 243 | for(G.first(e,s); G.valid(e); G.next(e)) |
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| 244 | { |
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| 245 | T rem=capacity[e]-flow[e]; |
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| 246 | if ( rem == 0 ) continue; |
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| 247 | Node w=G.head(e); |
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| 248 | if ( level[w] < n ) { |
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| 249 | if ( excess[w] == 0 && w!=t ) { |
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| 250 | next.set(w,active[level[w]]); |
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| 251 | active[level[w]]=w; |
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| 252 | } |
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| 253 | flow.set(e, capacity[e]); |
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| 254 | excess.set(w, excess[w]+rem); |
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| 255 | } |
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| 256 | } |
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| 257 | |
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| 258 | InEdgeIt f; |
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| 259 | for(G.first(f,s); G.valid(f); G.next(f)) |
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| 260 | { |
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| 261 | if ( flow[f] == 0 ) continue; |
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| 262 | Node w=G.head(f); |
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| 263 | if ( level[w] < n ) { |
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| 264 | if ( excess[w] == 0 && w!=t ) { |
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| 265 | next.set(w,active[level[w]]); |
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| 266 | active[level[w]]=w; |
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| 267 | } |
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| 268 | excess.set(w, excess[w]+flow[f]); |
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| 269 | flow.set(f, 0); |
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| 270 | } |
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| 271 | } |
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| 272 | } |
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| 273 | |
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| 274 | |
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| 275 | |
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| 276 | |
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| 277 | /* |
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| 278 | End of preprocessing |
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| 279 | */ |
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| 280 | |
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| 281 | |
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| 282 | |
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| 283 | /* |
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| 284 | Push/relabel on the highest level active nodes. |
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| 285 | */ |
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| 286 | while ( true ) { |
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| 287 | |
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| 288 | if ( b == 0 ) { |
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| 289 | if ( phase ) break; |
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| 290 | |
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| 291 | if ( !what_heur && !end && k > 0 ) { |
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| 292 | b=k; |
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| 293 | end=true; |
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| 294 | } else { |
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| 295 | phase=1; |
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| 296 | level.set(s,0); |
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| 297 | std::queue<Node> bfs_queue; |
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| 298 | bfs_queue.push(s); |
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| 299 | |
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| 300 | while (!bfs_queue.empty()) { |
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| 301 | |
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| 302 | Node v=bfs_queue.front(); |
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| 303 | bfs_queue.pop(); |
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| 304 | int l=level[v]+1; |
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| 305 | |
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[374] | 306 | if (res){ |
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| 307 | ResInEdgeIt e; |
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| 308 | for(res_graph.first(e,v); res_graph.valid(e); |
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| 309 | res_graph.next(e)) { |
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| 310 | Node u=res_graph.tail(e); |
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| 311 | if ( level[u] >= n ) { |
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| 312 | bfs_queue.push(u); |
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| 313 | level.set(u, l); |
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| 314 | if ( excess[u] > 0 ) { |
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| 315 | next.set(u,active[l]); |
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| 316 | active[l]=u; |
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| 317 | } |
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[370] | 318 | } |
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| 319 | } |
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[374] | 320 | } else { |
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| 321 | InEdgeIt e; |
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| 322 | for(G.first(e,v); G.valid(e); G.next(e)) { |
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| 323 | if ( capacity[e] == flow[e] ) continue; |
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| 324 | Node u=G.tail(e); |
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| 325 | if ( level[u] >= n ) { |
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| 326 | bfs_queue.push(u); |
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| 327 | level.set(u, l); |
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| 328 | if ( excess[u] > 0 ) { |
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| 329 | next.set(u,active[l]); |
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| 330 | active[l]=u; |
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| 331 | } |
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| 332 | } |
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| 333 | } |
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| 334 | |
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| 335 | OutEdgeIt f; |
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| 336 | for(G.first(f,v); G.valid(f); G.next(f)) { |
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| 337 | if ( 0 == flow[f] ) continue; |
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| 338 | Node u=G.head(f); |
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| 339 | if ( level[u] >= n ) { |
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| 340 | bfs_queue.push(u); |
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| 341 | level.set(u, l); |
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| 342 | if ( excess[u] > 0 ) { |
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| 343 | next.set(u,active[l]); |
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| 344 | active[l]=u; |
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| 345 | } |
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[370] | 346 | } |
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| 347 | } |
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| 348 | } |
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| 349 | } |
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| 350 | b=n-2; |
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| 351 | } |
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| 352 | |
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| 353 | } |
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| 354 | |
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| 355 | |
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| 356 | if ( !G.valid(active[b]) ) --b; |
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| 357 | else { |
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| 358 | end=false; |
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| 359 | |
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| 360 | Node w=active[b]; |
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| 361 | active[b]=next[w]; |
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| 362 | int lev=level[w]; |
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| 363 | T exc=excess[w]; |
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| 364 | int newlevel=n; //bound on the next level of w |
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| 365 | |
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| 366 | OutEdgeIt e; |
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| 367 | for(G.first(e,w); G.valid(e); G.next(e)) { |
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| 368 | |
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| 369 | if ( flow[e] == capacity[e] ) continue; |
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| 370 | Node v=G.head(e); |
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| 371 | //e=wv |
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| 372 | |
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| 373 | if( lev > level[v] ) { |
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| 374 | /*Push is allowed now*/ |
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| 375 | |
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| 376 | if ( excess[v]==0 && v!=t && v!=s ) { |
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| 377 | int lev_v=level[v]; |
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| 378 | next.set(v,active[lev_v]); |
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| 379 | active[lev_v]=v; |
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| 380 | } |
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| 381 | |
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| 382 | T cap=capacity[e]; |
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| 383 | T flo=flow[e]; |
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| 384 | T remcap=cap-flo; |
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| 385 | |
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| 386 | if ( remcap >= exc ) { |
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| 387 | /*A nonsaturating push.*/ |
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| 388 | |
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| 389 | flow.set(e, flo+exc); |
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| 390 | excess.set(v, excess[v]+exc); |
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| 391 | exc=0; |
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| 392 | break; |
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| 393 | |
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| 394 | } else { |
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| 395 | /*A saturating push.*/ |
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| 396 | |
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| 397 | flow.set(e, cap); |
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| 398 | excess.set(v, excess[v]+remcap); |
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| 399 | exc-=remcap; |
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| 400 | } |
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| 401 | } else if ( newlevel > level[v] ){ |
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| 402 | newlevel = level[v]; |
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| 403 | } |
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| 404 | |
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| 405 | } //for out edges wv |
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| 406 | |
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| 407 | |
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| 408 | if ( exc > 0 ) { |
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| 409 | InEdgeIt e; |
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| 410 | for(G.first(e,w); G.valid(e); G.next(e)) { |
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| 411 | |
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| 412 | if( flow[e] == 0 ) continue; |
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| 413 | Node v=G.tail(e); |
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| 414 | //e=vw |
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| 415 | |
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| 416 | if( lev > level[v] ) { |
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| 417 | /*Push is allowed now*/ |
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| 418 | |
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| 419 | if ( excess[v]==0 && v!=t && v!=s ) { |
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| 420 | int lev_v=level[v]; |
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| 421 | next.set(v,active[lev_v]); |
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| 422 | active[lev_v]=v; |
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| 423 | } |
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| 424 | |
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| 425 | T flo=flow[e]; |
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| 426 | |
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| 427 | if ( flo >= exc ) { |
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| 428 | /*A nonsaturating push.*/ |
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| 429 | |
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| 430 | flow.set(e, flo-exc); |
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| 431 | excess.set(v, excess[v]+exc); |
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| 432 | exc=0; |
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| 433 | break; |
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| 434 | } else { |
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| 435 | /*A saturating push.*/ |
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| 436 | |
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| 437 | excess.set(v, excess[v]+flo); |
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| 438 | exc-=flo; |
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| 439 | flow.set(e,0); |
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| 440 | } |
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| 441 | } else if ( newlevel > level[v] ) { |
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| 442 | newlevel = level[v]; |
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| 443 | } |
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| 444 | } //for in edges vw |
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| 445 | |
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| 446 | } // if w still has excess after the out edge for cycle |
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| 447 | |
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| 448 | excess.set(w, exc); |
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| 449 | |
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| 450 | /* |
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| 451 | Relabel |
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| 452 | */ |
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| 453 | |
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| 454 | |
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| 455 | if ( exc > 0 ) { |
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| 456 | //now 'lev' is the old level of w |
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| 457 | |
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| 458 | if ( phase ) { |
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| 459 | level.set(w,++newlevel); |
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| 460 | next.set(w,active[newlevel]); |
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| 461 | active[newlevel]=w; |
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| 462 | b=newlevel; |
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| 463 | } else { |
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| 464 | //unlacing starts |
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| 465 | Node right_n=right[w]; |
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| 466 | Node left_n=left[w]; |
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| 467 | |
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| 468 | if ( G.valid(right_n) ) { |
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| 469 | if ( G.valid(left_n) ) { |
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| 470 | right.set(left_n, right_n); |
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| 471 | left.set(right_n, left_n); |
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| 472 | } else { |
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| 473 | level_list[lev]=right_n; |
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| 474 | left.set(right_n, INVALID); |
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| 475 | } |
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| 476 | } else { |
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| 477 | if ( G.valid(left_n) ) { |
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| 478 | right.set(left_n, INVALID); |
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| 479 | } else { |
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| 480 | level_list[lev]=INVALID; |
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| 481 | } |
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| 482 | } |
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| 483 | //unlacing ends |
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| 484 | |
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| 485 | if ( !G.valid(level_list[lev]) ) { |
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| 486 | |
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| 487 | //gapping starts |
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| 488 | for (int i=lev; i!=k ; ) { |
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| 489 | Node v=level_list[++i]; |
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| 490 | while ( G.valid(v) ) { |
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| 491 | level.set(v,n); |
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| 492 | v=right[v]; |
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| 493 | } |
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| 494 | level_list[i]=INVALID; |
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| 495 | if ( !what_heur ) active[i]=INVALID; |
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| 496 | } |
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| 497 | |
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| 498 | level.set(w,n); |
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| 499 | b=lev-1; |
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| 500 | k=b; |
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| 501 | //gapping ends |
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| 502 | |
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| 503 | } else { |
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| 504 | |
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| 505 | if ( newlevel == n ) level.set(w,n); |
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| 506 | else { |
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| 507 | level.set(w,++newlevel); |
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| 508 | next.set(w,active[newlevel]); |
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| 509 | active[newlevel]=w; |
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| 510 | if ( what_heur ) b=newlevel; |
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| 511 | if ( k < newlevel ) ++k; //now k=newlevel |
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| 512 | Node first=level_list[newlevel]; |
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| 513 | if ( G.valid(first) ) left.set(first,w); |
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| 514 | right.set(w,first); |
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| 515 | left.set(w,INVALID); |
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| 516 | level_list[newlevel]=w; |
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| 517 | } |
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| 518 | } |
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| 519 | |
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| 520 | |
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| 521 | ++relabel; |
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| 522 | if ( relabel >= heur ) { |
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| 523 | relabel=0; |
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| 524 | if ( what_heur ) { |
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| 525 | what_heur=0; |
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| 526 | heur=heur0; |
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| 527 | end=false; |
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| 528 | } else { |
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| 529 | what_heur=1; |
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| 530 | heur=heur1; |
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| 531 | b=k; |
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| 532 | } |
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| 533 | } |
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| 534 | } //phase 0 |
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| 535 | |
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| 536 | |
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| 537 | } // if ( exc > 0 ) |
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| 538 | |
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| 539 | |
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| 540 | } // if stack[b] is nonempty |
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| 541 | |
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| 542 | } // while(true) |
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| 543 | |
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| 544 | |
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| 545 | value = excess[t]; |
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| 546 | /*Max flow value.*/ |
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| 547 | |
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| 548 | } //void run() |
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| 549 | |
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| 550 | |
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| 551 | |
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| 552 | |
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| 553 | |
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| 554 | /* |
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| 555 | Returns the maximum value of a flow. |
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| 556 | */ |
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| 557 | |
---|
| 558 | T flowValue() { |
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| 559 | return value; |
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| 560 | } |
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| 561 | |
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| 562 | |
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| 563 | FlowMap Flow() { |
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| 564 | return flow; |
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| 565 | } |
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| 566 | |
---|
| 567 | |
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| 568 | |
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| 569 | void Flow(FlowMap& _flow ) { |
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| 570 | NodeIt v; |
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| 571 | for(G.first(v) ; G.valid(v); G.next(v)) |
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| 572 | _flow.set(v,flow[v]); |
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| 573 | } |
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| 574 | |
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| 575 | |
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| 576 | |
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| 577 | /* |
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| 578 | Returns the minimum min cut, by a bfs from s in the residual graph. |
---|
| 579 | */ |
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| 580 | |
---|
| 581 | template<typename _CutMap> |
---|
| 582 | void minMinCut(_CutMap& M) { |
---|
| 583 | |
---|
| 584 | std::queue<Node> queue; |
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| 585 | |
---|
| 586 | M.set(s,true); |
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| 587 | queue.push(s); |
---|
| 588 | |
---|
| 589 | while (!queue.empty()) { |
---|
| 590 | Node w=queue.front(); |
---|
| 591 | queue.pop(); |
---|
| 592 | |
---|
| 593 | OutEdgeIt e; |
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| 594 | for(G.first(e,w) ; G.valid(e); G.next(e)) { |
---|
| 595 | Node v=G.head(e); |
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| 596 | if (!M[v] && flow[e] < capacity[e] ) { |
---|
| 597 | queue.push(v); |
---|
| 598 | M.set(v, true); |
---|
| 599 | } |
---|
| 600 | } |
---|
| 601 | |
---|
| 602 | InEdgeIt f; |
---|
| 603 | for(G.first(f,w) ; G.valid(f); G.next(f)) { |
---|
| 604 | Node v=G.tail(f); |
---|
| 605 | if (!M[v] && flow[f] > 0 ) { |
---|
| 606 | queue.push(v); |
---|
| 607 | M.set(v, true); |
---|
| 608 | } |
---|
| 609 | } |
---|
| 610 | } |
---|
| 611 | } |
---|
| 612 | |
---|
| 613 | |
---|
| 614 | |
---|
| 615 | /* |
---|
| 616 | Returns the maximum min cut, by a reverse bfs |
---|
| 617 | from t in the residual graph. |
---|
| 618 | */ |
---|
| 619 | |
---|
| 620 | template<typename _CutMap> |
---|
| 621 | void maxMinCut(_CutMap& M) { |
---|
| 622 | |
---|
| 623 | std::queue<Node> queue; |
---|
| 624 | |
---|
| 625 | M.set(t,true); |
---|
| 626 | queue.push(t); |
---|
| 627 | |
---|
| 628 | while (!queue.empty()) { |
---|
| 629 | Node w=queue.front(); |
---|
| 630 | queue.pop(); |
---|
| 631 | |
---|
| 632 | |
---|
| 633 | InEdgeIt e; |
---|
| 634 | for(G.first(e,w) ; G.valid(e); G.next(e)) { |
---|
| 635 | Node v=G.tail(e); |
---|
| 636 | if (!M[v] && flow[e] < capacity[e] ) { |
---|
| 637 | queue.push(v); |
---|
| 638 | M.set(v, true); |
---|
| 639 | } |
---|
| 640 | } |
---|
| 641 | |
---|
| 642 | OutEdgeIt f; |
---|
| 643 | for(G.first(f,w) ; G.valid(f); G.next(f)) { |
---|
| 644 | Node v=G.head(f); |
---|
| 645 | if (!M[v] && flow[f] > 0 ) { |
---|
| 646 | queue.push(v); |
---|
| 647 | M.set(v, true); |
---|
| 648 | } |
---|
| 649 | } |
---|
| 650 | } |
---|
| 651 | |
---|
| 652 | NodeIt v; |
---|
| 653 | for(G.first(v) ; G.valid(v); G.next(v)) { |
---|
| 654 | M.set(v, !M[v]); |
---|
| 655 | } |
---|
| 656 | |
---|
| 657 | } |
---|
| 658 | |
---|
| 659 | |
---|
| 660 | |
---|
| 661 | template<typename CutMap> |
---|
| 662 | void minCut(CutMap& M) { |
---|
| 663 | minMinCut(M); |
---|
| 664 | } |
---|
| 665 | |
---|
| 666 | |
---|
| 667 | void reset_target (Node _t) {t=_t;} |
---|
| 668 | void reset_source (Node _s) {s=_s;} |
---|
| 669 | |
---|
| 670 | template<typename _CapMap> |
---|
| 671 | void reset_cap (_CapMap _cap) {capacity=_cap;} |
---|
| 672 | |
---|
| 673 | template<typename _FlowMap> |
---|
| 674 | void reset_cap (_FlowMap _flow, bool _constzero) { |
---|
| 675 | flow=_flow; |
---|
| 676 | constzero=_constzero; |
---|
| 677 | } |
---|
| 678 | |
---|
| 679 | |
---|
| 680 | |
---|
| 681 | }; |
---|
| 682 | |
---|
| 683 | } //namespace hugo |
---|
| 684 | |
---|
[376] | 685 | #endif //PREFLOW_PROBA_H |
---|
[370] | 686 | |
---|
| 687 | |
---|
| 688 | |
---|
| 689 | |
---|