874 lines
38 KiB
C++
874 lines
38 KiB
C++
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// Copyright (c) 2006, Stephan Diederich
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//
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// This code may be used under either of the following two licences:
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//
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// Permission is hereby granted, free of charge, to any person
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// obtaining a copy of this software and associated documentation
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// files (the "Software"), to deal in the Software without
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// restriction, including without limitation the rights to use,
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// copy, modify, merge, publish, distribute, sublicense, and/or
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// sell copies of the Software, and to permit persons to whom the
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// Software is furnished to do so, subject to the following
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// conditions:
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//
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// The above copyright notice and this permission notice shall be
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// included in all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
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// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
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// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
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// OTHER DEALINGS IN THE SOFTWARE. OF SUCH DAMAGE.
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//
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// Or:
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//
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// Distributed under the Boost Software License, Version 1.0.
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// (See accompanying file LICENSE_1_0.txt or copy at
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// http://www.boost.org/LICENSE_1_0.txt)
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#ifndef BOOST_BOYKOV_KOLMOGOROV_MAX_FLOW_HPP
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#define BOOST_BOYKOV_KOLMOGOROV_MAX_FLOW_HPP
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#include <boost/config.hpp>
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#include <boost/assert.hpp>
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#include <vector>
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#include <list>
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#include <utility>
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#include <iosfwd>
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#include <algorithm> // for std::min and std::max
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#include <boost/pending/queue.hpp>
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#include <boost/limits.hpp>
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#include <boost/property_map/property_map.hpp>
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#include <boost/none_t.hpp>
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#include <boost/graph/graph_concepts.hpp>
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#include <boost/graph/named_function_params.hpp>
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#include <boost/graph/lookup_edge.hpp>
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#include <boost/concept/assert.hpp>
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// The algorithm impelemented here is described in:
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//
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// Boykov, Y., Kolmogorov, V. "An Experimental Comparison of Min-Cut/Max-Flow
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// Algorithms for Energy Minimization in Vision", In IEEE Transactions on
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// Pattern Analysis and Machine Intelligence, vol. 26, no. 9, pp. 1124-1137,
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// Sep 2004.
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//
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// For further reading, also see:
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//
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// Kolmogorov, V. "Graph Based Algorithms for Scene Reconstruction from Two or
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// More Views". PhD thesis, Cornell University, Sep 2003.
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namespace boost {
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namespace detail {
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template <class Graph,
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class EdgeCapacityMap,
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class ResidualCapacityEdgeMap,
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class ReverseEdgeMap,
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class PredecessorMap,
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class ColorMap,
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class DistanceMap,
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class IndexMap>
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class bk_max_flow {
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typedef typename property_traits<EdgeCapacityMap>::value_type tEdgeVal;
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typedef graph_traits<Graph> tGraphTraits;
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typedef typename tGraphTraits::vertex_iterator vertex_iterator;
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typedef typename tGraphTraits::vertex_descriptor vertex_descriptor;
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typedef typename tGraphTraits::edge_descriptor edge_descriptor;
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typedef typename tGraphTraits::edge_iterator edge_iterator;
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typedef typename tGraphTraits::out_edge_iterator out_edge_iterator;
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typedef boost::queue<vertex_descriptor> tQueue; //queue of vertices, used in adoption-stage
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typedef typename property_traits<ColorMap>::value_type tColorValue;
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typedef color_traits<tColorValue> tColorTraits;
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typedef typename property_traits<DistanceMap>::value_type tDistanceVal;
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public:
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bk_max_flow(Graph& g,
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EdgeCapacityMap cap,
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ResidualCapacityEdgeMap res,
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ReverseEdgeMap rev,
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PredecessorMap pre,
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ColorMap color,
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DistanceMap dist,
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IndexMap idx,
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vertex_descriptor src,
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vertex_descriptor sink):
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m_g(g),
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m_index_map(idx),
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m_cap_map(cap),
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m_res_cap_map(res),
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m_rev_edge_map(rev),
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m_pre_map(pre),
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m_tree_map(color),
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m_dist_map(dist),
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m_source(src),
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m_sink(sink),
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m_active_nodes(),
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m_in_active_list_vec(num_vertices(g), false),
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m_in_active_list_map(make_iterator_property_map(m_in_active_list_vec.begin(), m_index_map)),
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m_has_parent_vec(num_vertices(g), false),
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m_has_parent_map(make_iterator_property_map(m_has_parent_vec.begin(), m_index_map)),
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m_time_vec(num_vertices(g), 0),
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m_time_map(make_iterator_property_map(m_time_vec.begin(), m_index_map)),
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m_flow(0),
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m_time(1),
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m_last_grow_vertex(graph_traits<Graph>::null_vertex()){
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// initialize the color-map with gray-values
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vertex_iterator vi, v_end;
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for(boost::tie(vi, v_end) = vertices(m_g); vi != v_end; ++vi){
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set_tree(*vi, tColorTraits::gray());
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}
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// Initialize flow to zero which means initializing
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// the residual capacity equal to the capacity
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edge_iterator ei, e_end;
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for(boost::tie(ei, e_end) = edges(m_g); ei != e_end; ++ei) {
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put(m_res_cap_map, *ei, get(m_cap_map, *ei));
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BOOST_ASSERT(get(m_rev_edge_map, get(m_rev_edge_map, *ei)) == *ei); //check if the reverse edge map is build up properly
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}
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//init the search trees with the two terminals
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set_tree(m_source, tColorTraits::black());
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set_tree(m_sink, tColorTraits::white());
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put(m_time_map, m_source, 1);
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put(m_time_map, m_sink, 1);
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}
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tEdgeVal max_flow(){
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//augment direct paths from SOURCE->SINK and SOURCE->VERTEX->SINK
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augment_direct_paths();
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//start the main-loop
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while(true){
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bool path_found;
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edge_descriptor connecting_edge;
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boost::tie(connecting_edge, path_found) = grow(); //find a path from source to sink
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if(!path_found){
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//we're finished, no more paths were found
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break;
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}
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++m_time;
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augment(connecting_edge); //augment that path
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adopt(); //rebuild search tree structure
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}
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return m_flow;
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}
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// the complete class is protected, as we want access to members in
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// derived test-class (see test/boykov_kolmogorov_max_flow_test.cpp)
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protected:
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void augment_direct_paths(){
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// in a first step, we augment all direct paths from source->NODE->sink
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// and additionally paths from source->sink. This improves especially
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// graphcuts for segmentation, as most of the nodes have source/sink
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// connects but shouldn't have an impact on other maxflow problems
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// (this is done in grow() anyway)
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out_edge_iterator ei, e_end;
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for(boost::tie(ei, e_end) = out_edges(m_source, m_g); ei != e_end; ++ei){
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edge_descriptor from_source = *ei;
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vertex_descriptor current_node = target(from_source, m_g);
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if(current_node == m_sink){
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tEdgeVal cap = get(m_res_cap_map, from_source);
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put(m_res_cap_map, from_source, 0);
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m_flow += cap;
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continue;
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}
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edge_descriptor to_sink;
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bool is_there;
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boost::tie(to_sink, is_there) = lookup_edge(current_node, m_sink, m_g);
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if(is_there){
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tEdgeVal cap_from_source = get(m_res_cap_map, from_source);
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tEdgeVal cap_to_sink = get(m_res_cap_map, to_sink);
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if(cap_from_source > cap_to_sink){
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set_tree(current_node, tColorTraits::black());
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add_active_node(current_node);
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set_edge_to_parent(current_node, from_source);
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put(m_dist_map, current_node, 1);
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put(m_time_map, current_node, 1);
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// add stuff to flow and update residuals. we dont need to
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// update reverse_edges, as incoming/outgoing edges to/from
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// source/sink don't count for max-flow
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put(m_res_cap_map, from_source, get(m_res_cap_map, from_source) - cap_to_sink);
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put(m_res_cap_map, to_sink, 0);
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m_flow += cap_to_sink;
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} else if(cap_to_sink > 0){
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set_tree(current_node, tColorTraits::white());
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add_active_node(current_node);
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set_edge_to_parent(current_node, to_sink);
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put(m_dist_map, current_node, 1);
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put(m_time_map, current_node, 1);
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// add stuff to flow and update residuals. we dont need to update
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// reverse_edges, as incoming/outgoing edges to/from source/sink
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// don't count for max-flow
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put(m_res_cap_map, to_sink, get(m_res_cap_map, to_sink) - cap_from_source);
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put(m_res_cap_map, from_source, 0);
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m_flow += cap_from_source;
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}
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} else if(get(m_res_cap_map, from_source)){
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// there is no sink connect, so we can't augment this path, but to
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// avoid adding m_source to the active nodes, we just activate this
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// node and set the approciate things
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set_tree(current_node, tColorTraits::black());
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set_edge_to_parent(current_node, from_source);
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put(m_dist_map, current_node, 1);
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put(m_time_map, current_node, 1);
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add_active_node(current_node);
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}
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}
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for(boost::tie(ei, e_end) = out_edges(m_sink, m_g); ei != e_end; ++ei){
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edge_descriptor to_sink = get(m_rev_edge_map, *ei);
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vertex_descriptor current_node = source(to_sink, m_g);
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if(get(m_res_cap_map, to_sink)){
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set_tree(current_node, tColorTraits::white());
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set_edge_to_parent(current_node, to_sink);
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put(m_dist_map, current_node, 1);
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put(m_time_map, current_node, 1);
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add_active_node(current_node);
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}
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}
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}
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/**
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* Returns a pair of an edge and a boolean. if the bool is true, the
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* edge is a connection of a found path from s->t , read "the link" and
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* source(returnVal, m_g) is the end of the path found in the source-tree
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* target(returnVal, m_g) is the beginning of the path found in the sink-tree
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*/
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std::pair<edge_descriptor, bool> grow(){
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BOOST_ASSERT(m_orphans.empty());
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vertex_descriptor current_node;
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while((current_node = get_next_active_node()) != graph_traits<Graph>::null_vertex()){ //if there is one
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BOOST_ASSERT(get_tree(current_node) != tColorTraits::gray() &&
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(has_parent(current_node) ||
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current_node == m_source ||
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current_node == m_sink));
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if(get_tree(current_node) == tColorTraits::black()){
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//source tree growing
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out_edge_iterator ei, e_end;
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if(current_node != m_last_grow_vertex){
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m_last_grow_vertex = current_node;
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boost::tie(m_last_grow_edge_it, m_last_grow_edge_end) = out_edges(current_node, m_g);
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}
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for(; m_last_grow_edge_it != m_last_grow_edge_end; ++m_last_grow_edge_it) {
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edge_descriptor out_edge = *m_last_grow_edge_it;
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if(get(m_res_cap_map, out_edge) > 0){ //check if we have capacity left on this edge
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vertex_descriptor other_node = target(out_edge, m_g);
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if(get_tree(other_node) == tColorTraits::gray()){ //it's a free node
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set_tree(other_node, tColorTraits::black()); //aquire other node to our search tree
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set_edge_to_parent(other_node, out_edge); //set us as parent
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put(m_dist_map, other_node, get(m_dist_map, current_node) + 1); //and update the distance-heuristic
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put(m_time_map, other_node, get(m_time_map, current_node));
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add_active_node(other_node);
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} else if(get_tree(other_node) == tColorTraits::black()) {
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// we do this to get shorter paths. check if we are nearer to
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// the source as its parent is
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if(is_closer_to_terminal(current_node, other_node)){
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set_edge_to_parent(other_node, out_edge);
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put(m_dist_map, other_node, get(m_dist_map, current_node) + 1);
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put(m_time_map, other_node, get(m_time_map, current_node));
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}
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} else{
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BOOST_ASSERT(get_tree(other_node)==tColorTraits::white());
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//kewl, found a path from one to the other search tree, return
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// the connecting edge in src->sink dir
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return std::make_pair(out_edge, true);
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}
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}
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} //for all out-edges
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} //source-tree-growing
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else{
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BOOST_ASSERT(get_tree(current_node) == tColorTraits::white());
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out_edge_iterator ei, e_end;
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if(current_node != m_last_grow_vertex){
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m_last_grow_vertex = current_node;
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boost::tie(m_last_grow_edge_it, m_last_grow_edge_end) = out_edges(current_node, m_g);
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}
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for(; m_last_grow_edge_it != m_last_grow_edge_end; ++m_last_grow_edge_it){
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edge_descriptor in_edge = get(m_rev_edge_map, *m_last_grow_edge_it);
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if(get(m_res_cap_map, in_edge) > 0){ //check if there is capacity left
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vertex_descriptor other_node = source(in_edge, m_g);
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if(get_tree(other_node) == tColorTraits::gray()){ //it's a free node
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set_tree(other_node, tColorTraits::white()); //aquire that node to our search tree
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set_edge_to_parent(other_node, in_edge); //set us as parent
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add_active_node(other_node); //activate that node
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put(m_dist_map, other_node, get(m_dist_map, current_node) + 1); //set its distance
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put(m_time_map, other_node, get(m_time_map, current_node));//and time
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} else if(get_tree(other_node) == tColorTraits::white()){
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if(is_closer_to_terminal(current_node, other_node)){
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//we are closer to the sink than its parent is, so we "adopt" him
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set_edge_to_parent(other_node, in_edge);
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put(m_dist_map, other_node, get(m_dist_map, current_node) + 1);
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put(m_time_map, other_node, get(m_time_map, current_node));
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}
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} else{
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BOOST_ASSERT(get_tree(other_node)==tColorTraits::black());
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//kewl, found a path from one to the other search tree,
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// return the connecting edge in src->sink dir
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return std::make_pair(in_edge, true);
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}
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}
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} //for all out-edges
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} //sink-tree growing
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//all edges of that node are processed, and no more paths were found.
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// remove if from the front of the active queue
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finish_node(current_node);
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} //while active_nodes not empty
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//no active nodes anymore and no path found, we're done
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return std::make_pair(edge_descriptor(), false);
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}
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/**
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* augments path from s->t and updates residual graph
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* source(e, m_g) is the end of the path found in the source-tree
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* target(e, m_g) is the beginning of the path found in the sink-tree
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* this phase generates orphans on satured edges, if the attached verts are
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* from different search-trees orphans are ordered in distance to
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* sink/source. first the farest from the source are front_inserted into
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* the orphans list, and after that the sink-tree-orphans are
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* front_inserted. when going to adoption stage the orphans are popped_front,
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* and so we process the nearest verts to the terminals first
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*/
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void augment(edge_descriptor e) {
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BOOST_ASSERT(get_tree(target(e, m_g)) == tColorTraits::white());
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BOOST_ASSERT(get_tree(source(e, m_g)) == tColorTraits::black());
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BOOST_ASSERT(m_orphans.empty());
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const tEdgeVal bottleneck = find_bottleneck(e);
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//now we push the found flow through the path
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//for each edge we saturate we have to look for the verts that belong to that edge, one of them becomes an orphans
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//now process the connecting edge
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put(m_res_cap_map, e, get(m_res_cap_map, e) - bottleneck);
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BOOST_ASSERT(get(m_res_cap_map, e) >= 0);
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put(m_res_cap_map, get(m_rev_edge_map, e), get(m_res_cap_map, get(m_rev_edge_map, e)) + bottleneck);
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//now we follow the path back to the source
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vertex_descriptor current_node = source(e, m_g);
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while(current_node != m_source){
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edge_descriptor pred = get_edge_to_parent(current_node);
|
||
|
put(m_res_cap_map, pred, get(m_res_cap_map, pred) - bottleneck);
|
||
|
BOOST_ASSERT(get(m_res_cap_map, pred) >= 0);
|
||
|
put(m_res_cap_map, get(m_rev_edge_map, pred), get(m_res_cap_map, get(m_rev_edge_map, pred)) + bottleneck);
|
||
|
if(get(m_res_cap_map, pred) == 0){
|
||
|
set_no_parent(current_node);
|
||
|
m_orphans.push_front(current_node);
|
||
|
}
|
||
|
current_node = source(pred, m_g);
|
||
|
}
|
||
|
//then go forward in the sink-tree
|
||
|
current_node = target(e, m_g);
|
||
|
while(current_node != m_sink){
|
||
|
edge_descriptor pred = get_edge_to_parent(current_node);
|
||
|
put(m_res_cap_map, pred, get(m_res_cap_map, pred) - bottleneck);
|
||
|
BOOST_ASSERT(get(m_res_cap_map, pred) >= 0);
|
||
|
put(m_res_cap_map, get(m_rev_edge_map, pred), get(m_res_cap_map, get(m_rev_edge_map, pred)) + bottleneck);
|
||
|
if(get(m_res_cap_map, pred) == 0){
|
||
|
set_no_parent(current_node);
|
||
|
m_orphans.push_front(current_node);
|
||
|
}
|
||
|
current_node = target(pred, m_g);
|
||
|
}
|
||
|
//and add it to the max-flow
|
||
|
m_flow += bottleneck;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* returns the bottleneck of a s->t path (end_of_path is last vertex in
|
||
|
* source-tree, begin_of_path is first vertex in sink-tree)
|
||
|
*/
|
||
|
inline tEdgeVal find_bottleneck(edge_descriptor e){
|
||
|
BOOST_USING_STD_MIN();
|
||
|
tEdgeVal minimum_cap = get(m_res_cap_map, e);
|
||
|
vertex_descriptor current_node = source(e, m_g);
|
||
|
//first go back in the source tree
|
||
|
while(current_node != m_source){
|
||
|
edge_descriptor pred = get_edge_to_parent(current_node);
|
||
|
minimum_cap = min BOOST_PREVENT_MACRO_SUBSTITUTION(minimum_cap, get(m_res_cap_map, pred));
|
||
|
current_node = source(pred, m_g);
|
||
|
}
|
||
|
//then go forward in the sink-tree
|
||
|
current_node = target(e, m_g);
|
||
|
while(current_node != m_sink){
|
||
|
edge_descriptor pred = get_edge_to_parent(current_node);
|
||
|
minimum_cap = min BOOST_PREVENT_MACRO_SUBSTITUTION(minimum_cap, get(m_res_cap_map, pred));
|
||
|
current_node = target(pred, m_g);
|
||
|
}
|
||
|
return minimum_cap;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* rebuild search trees
|
||
|
* empty the queue of orphans, and find new parents for them or just drop
|
||
|
* them from the search trees
|
||
|
*/
|
||
|
void adopt(){
|
||
|
while(!m_orphans.empty() || !m_child_orphans.empty()){
|
||
|
vertex_descriptor current_node;
|
||
|
if(m_child_orphans.empty()){
|
||
|
//get the next orphan from the main-queue and remove it
|
||
|
current_node = m_orphans.front();
|
||
|
m_orphans.pop_front();
|
||
|
} else{
|
||
|
current_node = m_child_orphans.front();
|
||
|
m_child_orphans.pop();
|
||
|
}
|
||
|
if(get_tree(current_node) == tColorTraits::black()){
|
||
|
//we're in the source-tree
|
||
|
tDistanceVal min_distance = (std::numeric_limits<tDistanceVal>::max)();
|
||
|
edge_descriptor new_parent_edge;
|
||
|
out_edge_iterator ei, e_end;
|
||
|
for(boost::tie(ei, e_end) = out_edges(current_node, m_g); ei != e_end; ++ei){
|
||
|
const edge_descriptor in_edge = get(m_rev_edge_map, *ei);
|
||
|
BOOST_ASSERT(target(in_edge, m_g) == current_node); //we should be the target of this edge
|
||
|
if(get(m_res_cap_map, in_edge) > 0){
|
||
|
vertex_descriptor other_node = source(in_edge, m_g);
|
||
|
if(get_tree(other_node) == tColorTraits::black() && has_source_connect(other_node)){
|
||
|
if(get(m_dist_map, other_node) < min_distance){
|
||
|
min_distance = get(m_dist_map, other_node);
|
||
|
new_parent_edge = in_edge;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
if(min_distance != (std::numeric_limits<tDistanceVal>::max)()){
|
||
|
set_edge_to_parent(current_node, new_parent_edge);
|
||
|
put(m_dist_map, current_node, min_distance + 1);
|
||
|
put(m_time_map, current_node, m_time);
|
||
|
} else{
|
||
|
put(m_time_map, current_node, 0);
|
||
|
for(boost::tie(ei, e_end) = out_edges(current_node, m_g); ei != e_end; ++ei){
|
||
|
edge_descriptor in_edge = get(m_rev_edge_map, *ei);
|
||
|
vertex_descriptor other_node = source(in_edge, m_g);
|
||
|
if(get_tree(other_node) == tColorTraits::black() && other_node != m_source){
|
||
|
if(get(m_res_cap_map, in_edge) > 0){
|
||
|
add_active_node(other_node);
|
||
|
}
|
||
|
if(has_parent(other_node) && source(get_edge_to_parent(other_node), m_g) == current_node){
|
||
|
//we are the parent of that node
|
||
|
//it has to find a new parent, too
|
||
|
set_no_parent(other_node);
|
||
|
m_child_orphans.push(other_node);
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
set_tree(current_node, tColorTraits::gray());
|
||
|
} //no parent found
|
||
|
} //source-tree-adoption
|
||
|
else{
|
||
|
//now we should be in the sink-tree, check that...
|
||
|
BOOST_ASSERT(get_tree(current_node) == tColorTraits::white());
|
||
|
out_edge_iterator ei, e_end;
|
||
|
edge_descriptor new_parent_edge;
|
||
|
tDistanceVal min_distance = (std::numeric_limits<tDistanceVal>::max)();
|
||
|
for(boost::tie(ei, e_end) = out_edges(current_node, m_g); ei != e_end; ++ei){
|
||
|
const edge_descriptor out_edge = *ei;
|
||
|
if(get(m_res_cap_map, out_edge) > 0){
|
||
|
const vertex_descriptor other_node = target(out_edge, m_g);
|
||
|
if(get_tree(other_node) == tColorTraits::white() && has_sink_connect(other_node))
|
||
|
if(get(m_dist_map, other_node) < min_distance){
|
||
|
min_distance = get(m_dist_map, other_node);
|
||
|
new_parent_edge = out_edge;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
if(min_distance != (std::numeric_limits<tDistanceVal>::max)()){
|
||
|
set_edge_to_parent(current_node, new_parent_edge);
|
||
|
put(m_dist_map, current_node, min_distance + 1);
|
||
|
put(m_time_map, current_node, m_time);
|
||
|
} else{
|
||
|
put(m_time_map, current_node, 0);
|
||
|
for(boost::tie(ei, e_end) = out_edges(current_node, m_g); ei != e_end; ++ei){
|
||
|
const edge_descriptor out_edge = *ei;
|
||
|
const vertex_descriptor other_node = target(out_edge, m_g);
|
||
|
if(get_tree(other_node) == tColorTraits::white() && other_node != m_sink){
|
||
|
if(get(m_res_cap_map, out_edge) > 0){
|
||
|
add_active_node(other_node);
|
||
|
}
|
||
|
if(has_parent(other_node) && target(get_edge_to_parent(other_node), m_g) == current_node){
|
||
|
//we were it's parent, so it has to find a new one, too
|
||
|
set_no_parent(other_node);
|
||
|
m_child_orphans.push(other_node);
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
set_tree(current_node, tColorTraits::gray());
|
||
|
} //no parent found
|
||
|
} //sink-tree adoption
|
||
|
} //while !orphans.empty()
|
||
|
} //adopt
|
||
|
|
||
|
/**
|
||
|
* return next active vertex if there is one, otherwise a null_vertex
|
||
|
*/
|
||
|
inline vertex_descriptor get_next_active_node(){
|
||
|
while(true){
|
||
|
if(m_active_nodes.empty())
|
||
|
return graph_traits<Graph>::null_vertex();
|
||
|
vertex_descriptor v = m_active_nodes.front();
|
||
|
|
||
|
//if it has no parent, this node can't be active (if its not source or sink)
|
||
|
if(!has_parent(v) && v != m_source && v != m_sink){
|
||
|
m_active_nodes.pop();
|
||
|
put(m_in_active_list_map, v, false);
|
||
|
} else{
|
||
|
BOOST_ASSERT(get_tree(v) == tColorTraits::black() || get_tree(v) == tColorTraits::white());
|
||
|
return v;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* adds v as an active vertex, but only if its not in the list already
|
||
|
*/
|
||
|
inline void add_active_node(vertex_descriptor v){
|
||
|
BOOST_ASSERT(get_tree(v) != tColorTraits::gray());
|
||
|
if(get(m_in_active_list_map, v)){
|
||
|
if (m_last_grow_vertex == v) {
|
||
|
m_last_grow_vertex = graph_traits<Graph>::null_vertex();
|
||
|
}
|
||
|
return;
|
||
|
} else{
|
||
|
put(m_in_active_list_map, v, true);
|
||
|
m_active_nodes.push(v);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* finish_node removes a node from the front of the active queue (its called in grow phase, if no more paths can be found using this node)
|
||
|
*/
|
||
|
inline void finish_node(vertex_descriptor v){
|
||
|
BOOST_ASSERT(m_active_nodes.front() == v);
|
||
|
m_active_nodes.pop();
|
||
|
put(m_in_active_list_map, v, false);
|
||
|
m_last_grow_vertex = graph_traits<Graph>::null_vertex();
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* removes a vertex from the queue of active nodes (actually this does nothing,
|
||
|
* but checks if this node has no parent edge, as this is the criteria for
|
||
|
* being no more active)
|
||
|
*/
|
||
|
inline void remove_active_node(vertex_descriptor v){
|
||
|
BOOST_ASSERT(!has_parent(v));
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* returns the search tree of v; tColorValue::black() for source tree,
|
||
|
* white() for sink tree, gray() for no tree
|
||
|
*/
|
||
|
inline tColorValue get_tree(vertex_descriptor v) const {
|
||
|
return get(m_tree_map, v);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* sets search tree of v; tColorValue::black() for source tree, white()
|
||
|
* for sink tree, gray() for no tree
|
||
|
*/
|
||
|
inline void set_tree(vertex_descriptor v, tColorValue t){
|
||
|
put(m_tree_map, v, t);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* returns edge to parent vertex of v;
|
||
|
*/
|
||
|
inline edge_descriptor get_edge_to_parent(vertex_descriptor v) const{
|
||
|
return get(m_pre_map, v);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* returns true if the edge stored in m_pre_map[v] is a valid entry
|
||
|
*/
|
||
|
inline bool has_parent(vertex_descriptor v) const{
|
||
|
return get(m_has_parent_map, v);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* sets edge to parent vertex of v;
|
||
|
*/
|
||
|
inline void set_edge_to_parent(vertex_descriptor v, edge_descriptor f_edge_to_parent){
|
||
|
BOOST_ASSERT(get(m_res_cap_map, f_edge_to_parent) > 0);
|
||
|
put(m_pre_map, v, f_edge_to_parent);
|
||
|
put(m_has_parent_map, v, true);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* removes the edge to parent of v (this is done by invalidating the
|
||
|
* entry an additional map)
|
||
|
*/
|
||
|
inline void set_no_parent(vertex_descriptor v){
|
||
|
put(m_has_parent_map, v, false);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* checks if vertex v has a connect to the sink-vertex (@var m_sink)
|
||
|
* @param v the vertex which is checked
|
||
|
* @return true if a path to the sink was found, false if not
|
||
|
*/
|
||
|
inline bool has_sink_connect(vertex_descriptor v){
|
||
|
tDistanceVal current_distance = 0;
|
||
|
vertex_descriptor current_vertex = v;
|
||
|
while(true){
|
||
|
if(get(m_time_map, current_vertex) == m_time){
|
||
|
//we found a node which was already checked this round. use it for distance calculations
|
||
|
current_distance += get(m_dist_map, current_vertex);
|
||
|
break;
|
||
|
}
|
||
|
if(current_vertex == m_sink){
|
||
|
put(m_time_map, m_sink, m_time);
|
||
|
break;
|
||
|
}
|
||
|
if(has_parent(current_vertex)){
|
||
|
//it has a parent, so get it
|
||
|
current_vertex = target(get_edge_to_parent(current_vertex), m_g);
|
||
|
++current_distance;
|
||
|
} else{
|
||
|
//no path found
|
||
|
return false;
|
||
|
}
|
||
|
}
|
||
|
current_vertex=v;
|
||
|
while(get(m_time_map, current_vertex) != m_time){
|
||
|
put(m_dist_map, current_vertex, current_distance);
|
||
|
--current_distance;
|
||
|
put(m_time_map, current_vertex, m_time);
|
||
|
current_vertex = target(get_edge_to_parent(current_vertex), m_g);
|
||
|
}
|
||
|
return true;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* checks if vertex v has a connect to the source-vertex (@var m_source)
|
||
|
* @param v the vertex which is checked
|
||
|
* @return true if a path to the source was found, false if not
|
||
|
*/
|
||
|
inline bool has_source_connect(vertex_descriptor v){
|
||
|
tDistanceVal current_distance = 0;
|
||
|
vertex_descriptor current_vertex = v;
|
||
|
while(true){
|
||
|
if(get(m_time_map, current_vertex) == m_time){
|
||
|
//we found a node which was already checked this round. use it for distance calculations
|
||
|
current_distance += get(m_dist_map, current_vertex);
|
||
|
break;
|
||
|
}
|
||
|
if(current_vertex == m_source){
|
||
|
put(m_time_map, m_source, m_time);
|
||
|
break;
|
||
|
}
|
||
|
if(has_parent(current_vertex)){
|
||
|
//it has a parent, so get it
|
||
|
current_vertex = source(get_edge_to_parent(current_vertex), m_g);
|
||
|
++current_distance;
|
||
|
} else{
|
||
|
//no path found
|
||
|
return false;
|
||
|
}
|
||
|
}
|
||
|
current_vertex=v;
|
||
|
while(get(m_time_map, current_vertex) != m_time){
|
||
|
put(m_dist_map, current_vertex, current_distance);
|
||
|
--current_distance;
|
||
|
put(m_time_map, current_vertex, m_time);
|
||
|
current_vertex = source(get_edge_to_parent(current_vertex), m_g);
|
||
|
}
|
||
|
return true;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* returns true, if p is closer to a terminal than q
|
||
|
*/
|
||
|
inline bool is_closer_to_terminal(vertex_descriptor p, vertex_descriptor q){
|
||
|
//checks the timestamps first, to build no cycles, and after that the real distance
|
||
|
return (get(m_time_map, q) <= get(m_time_map, p) &&
|
||
|
get(m_dist_map, q) > get(m_dist_map, p)+1);
|
||
|
}
|
||
|
|
||
|
////////
|
||
|
// member vars
|
||
|
////////
|
||
|
Graph& m_g;
|
||
|
IndexMap m_index_map;
|
||
|
EdgeCapacityMap m_cap_map;
|
||
|
ResidualCapacityEdgeMap m_res_cap_map;
|
||
|
ReverseEdgeMap m_rev_edge_map;
|
||
|
PredecessorMap m_pre_map; //stores paths found in the growth stage
|
||
|
ColorMap m_tree_map; //maps each vertex into one of the two search tree or none (gray())
|
||
|
DistanceMap m_dist_map; //stores distance to source/sink nodes
|
||
|
vertex_descriptor m_source;
|
||
|
vertex_descriptor m_sink;
|
||
|
|
||
|
tQueue m_active_nodes;
|
||
|
std::vector<bool> m_in_active_list_vec;
|
||
|
iterator_property_map<std::vector<bool>::iterator, IndexMap> m_in_active_list_map;
|
||
|
|
||
|
std::list<vertex_descriptor> m_orphans;
|
||
|
tQueue m_child_orphans; // we use a second queuqe for child orphans, as they are FIFO processed
|
||
|
|
||
|
std::vector<bool> m_has_parent_vec;
|
||
|
iterator_property_map<std::vector<bool>::iterator, IndexMap> m_has_parent_map;
|
||
|
|
||
|
std::vector<long> m_time_vec; //timestamp of each node, used for sink/source-path calculations
|
||
|
iterator_property_map<std::vector<long>::iterator, IndexMap> m_time_map;
|
||
|
tEdgeVal m_flow;
|
||
|
long m_time;
|
||
|
vertex_descriptor m_last_grow_vertex;
|
||
|
out_edge_iterator m_last_grow_edge_it;
|
||
|
out_edge_iterator m_last_grow_edge_end;
|
||
|
};
|
||
|
|
||
|
} //namespace boost::detail
|
||
|
|
||
|
/**
|
||
|
* non-named-parameter version, given everything
|
||
|
* this is the catch all version
|
||
|
*/
|
||
|
template<class Graph,
|
||
|
class CapacityEdgeMap,
|
||
|
class ResidualCapacityEdgeMap,
|
||
|
class ReverseEdgeMap, class PredecessorMap,
|
||
|
class ColorMap,
|
||
|
class DistanceMap,
|
||
|
class IndexMap>
|
||
|
typename property_traits<CapacityEdgeMap>::value_type
|
||
|
boykov_kolmogorov_max_flow(Graph& g,
|
||
|
CapacityEdgeMap cap,
|
||
|
ResidualCapacityEdgeMap res_cap,
|
||
|
ReverseEdgeMap rev_map,
|
||
|
PredecessorMap pre_map,
|
||
|
ColorMap color,
|
||
|
DistanceMap dist,
|
||
|
IndexMap idx,
|
||
|
typename graph_traits<Graph>::vertex_descriptor src,
|
||
|
typename graph_traits<Graph>::vertex_descriptor sink)
|
||
|
{
|
||
|
typedef typename graph_traits<Graph>::vertex_descriptor vertex_descriptor;
|
||
|
typedef typename graph_traits<Graph>::edge_descriptor edge_descriptor;
|
||
|
|
||
|
//as this method is the last one before we instantiate the solver, we do the concept checks here
|
||
|
BOOST_CONCEPT_ASSERT(( VertexListGraphConcept<Graph> )); //to have vertices(), num_vertices(),
|
||
|
BOOST_CONCEPT_ASSERT(( EdgeListGraphConcept<Graph> )); //to have edges()
|
||
|
BOOST_CONCEPT_ASSERT(( IncidenceGraphConcept<Graph> )); //to have source(), target() and out_edges()
|
||
|
BOOST_CONCEPT_ASSERT(( ReadablePropertyMapConcept<CapacityEdgeMap, edge_descriptor> )); //read flow-values from edges
|
||
|
BOOST_CONCEPT_ASSERT(( ReadWritePropertyMapConcept<ResidualCapacityEdgeMap, edge_descriptor> )); //write flow-values to residuals
|
||
|
BOOST_CONCEPT_ASSERT(( ReadablePropertyMapConcept<ReverseEdgeMap, edge_descriptor> )); //read out reverse edges
|
||
|
BOOST_CONCEPT_ASSERT(( ReadWritePropertyMapConcept<PredecessorMap, vertex_descriptor> )); //store predecessor there
|
||
|
BOOST_CONCEPT_ASSERT(( ReadWritePropertyMapConcept<ColorMap, vertex_descriptor> )); //write corresponding tree
|
||
|
BOOST_CONCEPT_ASSERT(( ReadWritePropertyMapConcept<DistanceMap, vertex_descriptor> )); //write distance to source/sink
|
||
|
BOOST_CONCEPT_ASSERT(( ReadablePropertyMapConcept<IndexMap, vertex_descriptor> )); //get index 0...|V|-1
|
||
|
BOOST_ASSERT(num_vertices(g) >= 2 && src != sink);
|
||
|
|
||
|
detail::bk_max_flow<
|
||
|
Graph, CapacityEdgeMap, ResidualCapacityEdgeMap, ReverseEdgeMap,
|
||
|
PredecessorMap, ColorMap, DistanceMap, IndexMap
|
||
|
> algo(g, cap, res_cap, rev_map, pre_map, color, dist, idx, src, sink);
|
||
|
|
||
|
return algo.max_flow();
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* non-named-parameter version, given capacity, residucal_capacity,
|
||
|
* reverse_edges, and an index map.
|
||
|
*/
|
||
|
template<class Graph,
|
||
|
class CapacityEdgeMap,
|
||
|
class ResidualCapacityEdgeMap,
|
||
|
class ReverseEdgeMap,
|
||
|
class IndexMap>
|
||
|
typename property_traits<CapacityEdgeMap>::value_type
|
||
|
boykov_kolmogorov_max_flow(Graph& g,
|
||
|
CapacityEdgeMap cap,
|
||
|
ResidualCapacityEdgeMap res_cap,
|
||
|
ReverseEdgeMap rev,
|
||
|
IndexMap idx,
|
||
|
typename graph_traits<Graph>::vertex_descriptor src,
|
||
|
typename graph_traits<Graph>::vertex_descriptor sink)
|
||
|
{
|
||
|
typename graph_traits<Graph>::vertices_size_type n_verts = num_vertices(g);
|
||
|
std::vector<typename graph_traits<Graph>::edge_descriptor> predecessor_vec(n_verts);
|
||
|
std::vector<default_color_type> color_vec(n_verts);
|
||
|
std::vector<typename graph_traits<Graph>::vertices_size_type> distance_vec(n_verts);
|
||
|
return
|
||
|
boykov_kolmogorov_max_flow(
|
||
|
g, cap, res_cap, rev,
|
||
|
make_iterator_property_map(predecessor_vec.begin(), idx),
|
||
|
make_iterator_property_map(color_vec.begin(), idx),
|
||
|
make_iterator_property_map(distance_vec.begin(), idx),
|
||
|
idx, src, sink);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* non-named-parameter version, some given: capacity, residual_capacity,
|
||
|
* reverse_edges, color_map and an index map. Use this if you are interested in
|
||
|
* the minimum cut, as the color map provides that info.
|
||
|
*/
|
||
|
template<class Graph,
|
||
|
class CapacityEdgeMap,
|
||
|
class ResidualCapacityEdgeMap,
|
||
|
class ReverseEdgeMap,
|
||
|
class ColorMap,
|
||
|
class IndexMap>
|
||
|
typename property_traits<CapacityEdgeMap>::value_type
|
||
|
boykov_kolmogorov_max_flow(Graph& g,
|
||
|
CapacityEdgeMap cap,
|
||
|
ResidualCapacityEdgeMap res_cap,
|
||
|
ReverseEdgeMap rev,
|
||
|
ColorMap color,
|
||
|
IndexMap idx,
|
||
|
typename graph_traits<Graph>::vertex_descriptor src,
|
||
|
typename graph_traits<Graph>::vertex_descriptor sink)
|
||
|
{
|
||
|
typename graph_traits<Graph>::vertices_size_type n_verts = num_vertices(g);
|
||
|
std::vector<typename graph_traits<Graph>::edge_descriptor> predecessor_vec(n_verts);
|
||
|
std::vector<typename graph_traits<Graph>::vertices_size_type> distance_vec(n_verts);
|
||
|
return
|
||
|
boykov_kolmogorov_max_flow(
|
||
|
g, cap, res_cap, rev,
|
||
|
make_iterator_property_map(predecessor_vec.begin(), idx),
|
||
|
color,
|
||
|
make_iterator_property_map(distance_vec.begin(), idx),
|
||
|
idx, src, sink);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* named-parameter version, some given
|
||
|
*/
|
||
|
template<class Graph, class P, class T, class R>
|
||
|
typename property_traits<typename property_map<Graph, edge_capacity_t>::const_type>::value_type
|
||
|
boykov_kolmogorov_max_flow(Graph& g,
|
||
|
typename graph_traits<Graph>::vertex_descriptor src,
|
||
|
typename graph_traits<Graph>::vertex_descriptor sink,
|
||
|
const bgl_named_params<P, T, R>& params)
|
||
|
{
|
||
|
return
|
||
|
boykov_kolmogorov_max_flow(
|
||
|
g,
|
||
|
choose_const_pmap(get_param(params, edge_capacity), g, edge_capacity),
|
||
|
choose_pmap(get_param(params, edge_residual_capacity), g, edge_residual_capacity),
|
||
|
choose_const_pmap(get_param(params, edge_reverse), g, edge_reverse),
|
||
|
choose_pmap(get_param(params, vertex_predecessor), g, vertex_predecessor),
|
||
|
choose_pmap(get_param(params, vertex_color), g, vertex_color),
|
||
|
choose_pmap(get_param(params, vertex_distance), g, vertex_distance),
|
||
|
choose_const_pmap(get_param(params, vertex_index), g, vertex_index),
|
||
|
src, sink);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* named-parameter version, none given
|
||
|
*/
|
||
|
template<class Graph>
|
||
|
typename property_traits<typename property_map<Graph, edge_capacity_t>::const_type>::value_type
|
||
|
boykov_kolmogorov_max_flow(Graph& g,
|
||
|
typename graph_traits<Graph>::vertex_descriptor src,
|
||
|
typename graph_traits<Graph>::vertex_descriptor sink)
|
||
|
{
|
||
|
bgl_named_params<int, buffer_param_t> params(0); // bogus empty param
|
||
|
return boykov_kolmogorov_max_flow(g, src, sink, params);
|
||
|
}
|
||
|
|
||
|
} // namespace boost
|
||
|
|
||
|
#endif // BOOST_BOYKOV_KOLMOGOROV_MAX_FLOW_HPP
|
||
|
|