williamr@2: //=======================================================================
williamr@2: // Copyright 2001 University of Notre Dame.
williamr@2: // Authors: Jeremy G. Siek and Lie-Quan Lee
williamr@2: //
williamr@2: // Distributed under the Boost Software License, Version 1.0. (See
williamr@2: // accompanying file LICENSE_1_0.txt or copy at
williamr@2: // http://www.boost.org/LICENSE_1_0.txt)
williamr@2: //=======================================================================
williamr@2: 
williamr@2: #ifndef BOOST_SUBGRAPH_HPP
williamr@2: #define BOOST_SUBGRAPH_HPP
williamr@2: 
williamr@2: // UNDER CONSTRUCTION
williamr@2: 
williamr@2: #include <boost/config.hpp>
williamr@2: #include <list>
williamr@2: #include <vector>
williamr@2: #include <map>
williamr@2: #include <cassert>
williamr@2: #include <boost/graph/graph_traits.hpp>
williamr@2: #include <boost/graph/properties.hpp>
williamr@2: #include <boost/iterator/indirect_iterator.hpp>
williamr@2: 
williamr@2: #include <boost/static_assert.hpp>
williamr@2: #include <boost/type_traits/is_same.hpp>
williamr@2: 
williamr@2: namespace boost {
williamr@2: 
williamr@2:   struct subgraph_tag { };
williamr@2: 
williamr@2:   // Invariants of an induced subgraph:
williamr@2:   //   - If vertex u is in subgraph g, then u must be in g.parent().
williamr@2:   //   - If edge e is in subgraph g, then e must be in g.parent().
williamr@2:   //   - If edge e=(u,v) is in the root graph, then edge e
williamr@2:   //     is also in any subgraph that contains both vertex u and v.
williamr@2: 
williamr@2:   // The Graph template parameter must have a vertex_index
williamr@2:   // and edge_index internal property. It is assumed that
williamr@2:   // the vertex indices are assigned automatically by the
williamr@2:   // graph during a call to add_vertex(). It is not
williamr@2:   // assumed that the edge vertices are assigned automatically,
williamr@2:   // they are explicitly assigned here.
williamr@2: 
williamr@2:   template <typename Graph>
williamr@2:   class subgraph {
williamr@2:     typedef graph_traits<Graph> Traits;
williamr@2:     typedef std::list<subgraph<Graph>*> ChildrenList;
williamr@2:   public:
williamr@2:     // Graph requirements
williamr@2:     typedef typename Traits::vertex_descriptor         vertex_descriptor;
williamr@2:     typedef typename Traits::edge_descriptor           edge_descriptor;
williamr@2:     typedef typename Traits::directed_category         directed_category;
williamr@2:     typedef typename Traits::edge_parallel_category    edge_parallel_category;
williamr@2:     typedef typename Traits::traversal_category        traversal_category;
williamr@2: 
williamr@2:     static vertex_descriptor null_vertex()
williamr@2:     {
williamr@2:       return Traits::null_vertex();
williamr@2:     }
williamr@2: 
williamr@2: 
williamr@2:     // IncidenceGraph requirements
williamr@2:     typedef typename Traits::out_edge_iterator         out_edge_iterator;
williamr@2:     typedef typename Traits::degree_size_type          degree_size_type;
williamr@2: 
williamr@2:     // AdjacencyGraph requirements
williamr@2:     typedef typename Traits::adjacency_iterator        adjacency_iterator;
williamr@2: 
williamr@2:     // VertexListGraph requirements
williamr@2:     typedef typename Traits::vertex_iterator           vertex_iterator;
williamr@2:     typedef typename Traits::vertices_size_type        vertices_size_type;
williamr@2: 
williamr@2:     // EdgeListGraph requirements
williamr@2:     typedef typename Traits::edge_iterator             edge_iterator;
williamr@2:     typedef typename Traits::edges_size_type           edges_size_type;
williamr@2: 
williamr@2:     typedef typename Traits::in_edge_iterator          in_edge_iterator;
williamr@2: 
williamr@2:     typedef typename Graph::edge_property_type         edge_property_type;
williamr@2:     typedef typename Graph::vertex_property_type       vertex_property_type;
williamr@2:     typedef subgraph_tag                               graph_tag;
williamr@2:     typedef Graph                                      graph_type;
williamr@2:     typedef typename Graph::graph_property_type        graph_property_type;
williamr@2: 
williamr@2:     // Constructors
williamr@2: 
williamr@2:     // Create the main graph, the root of the subgraph tree
williamr@2:     subgraph()
williamr@2:       : m_parent(0), m_edge_counter(0)
williamr@2:     { }
williamr@2:     subgraph(const graph_property_type& p)
williamr@2:       : m_graph(p), m_parent(0), m_edge_counter(0)
williamr@2:     { }
williamr@2:     subgraph(vertices_size_type n,
williamr@2:              const graph_property_type& p = graph_property_type())
williamr@2:       : m_graph(n, p), m_parent(0), m_edge_counter(0), m_global_vertex(n)
williamr@2:     {
williamr@2:       typename Graph::vertex_iterator v, v_end;
williamr@2:       vertices_size_type i = 0;
williamr@2:       for (tie(v, v_end) = vertices(m_graph); v != v_end; ++v)
williamr@2:         m_global_vertex[i++] = *v;
williamr@2:     }
williamr@2: 
williamr@2:     // copy constructor
williamr@2:     subgraph(const subgraph& x)
williamr@2:       : m_graph(x.m_graph), m_parent(x.m_parent),
williamr@2:       m_edge_counter(x.m_edge_counter),
williamr@2:       m_global_vertex(x.m_global_vertex),
williamr@2:       m_global_edge(x.m_global_edge)
williamr@2:     {
williamr@2:       // Do a deep copy
williamr@2:       for (typename ChildrenList::const_iterator i = x.m_children.begin();
williamr@2:            i != x.m_children.end(); ++i)
williamr@2:         m_children.push_back(new subgraph<Graph>( **i ));
williamr@2:     }
williamr@2: 
williamr@2: 
williamr@2:     ~subgraph() {
williamr@2:       for (typename ChildrenList::iterator i = m_children.begin();
williamr@2:            i != m_children.end(); ++i)
williamr@2:         delete *i;
williamr@2:     }
williamr@2: 
williamr@2: 
williamr@2:     // Create a subgraph
williamr@2:     subgraph<Graph>& create_subgraph() {
williamr@2:       m_children.push_back(new subgraph<Graph>());
williamr@2:       m_children.back()->m_parent = this;
williamr@2:       return *m_children.back();
williamr@2:     }
williamr@2: 
williamr@2:     // Create a subgraph with the specified vertex set.
williamr@2:     template <typename VertexIterator>
williamr@2:     subgraph<Graph>& create_subgraph(VertexIterator first,
williamr@2:                                      VertexIterator last)
williamr@2:     {
williamr@2:       m_children.push_back(new subgraph<Graph>());
williamr@2:       m_children.back()->m_parent = this;
williamr@2:       for (; first != last; ++first)
williamr@2:         add_vertex(*first, *m_children.back());
williamr@2:       return *m_children.back();
williamr@2:     }
williamr@2: 
williamr@2:     // local <-> global descriptor conversion functions
williamr@2:     vertex_descriptor local_to_global(vertex_descriptor u_local) const
williamr@2:     {
williamr@2:       return m_global_vertex[u_local];
williamr@2:     }
williamr@2:     vertex_descriptor global_to_local(vertex_descriptor u_global) const
williamr@2:     {
williamr@2:       vertex_descriptor u_local; bool in_subgraph;
williamr@2:       tie(u_local, in_subgraph) = this->find_vertex(u_global);
williamr@2:       assert(in_subgraph == true);
williamr@2:       return u_local;
williamr@2:     }
williamr@2:     edge_descriptor local_to_global(edge_descriptor e_local) const
williamr@2:     {
williamr@2:       return m_global_edge[get(get(edge_index, m_graph), e_local)];
williamr@2:     }
williamr@2:     edge_descriptor global_to_local(edge_descriptor e_global) const
williamr@2:     {
williamr@2:       return
williamr@2:         (*m_local_edge.find(get(get(edge_index, root().m_graph), e_global))).second;
williamr@2:     }
williamr@2: 
williamr@2:     // Is vertex u (of the root graph) contained in this subgraph?
williamr@2:     // If so, return the matching local vertex.
williamr@2:     std::pair<vertex_descriptor, bool>
williamr@2:     find_vertex(vertex_descriptor u_global) const
williamr@2:     {
williamr@2:       typename std::map<vertex_descriptor, vertex_descriptor>::const_iterator
williamr@2:         i = m_local_vertex.find(u_global);
williamr@2:       bool valid = i != m_local_vertex.end();
williamr@2:       return std::make_pair((valid ? (*i).second : null_vertex()), valid);
williamr@2:     }
williamr@2: 
williamr@2:     // Return the parent graph.
williamr@2:     subgraph& parent() { return *m_parent; }
williamr@2:     const subgraph& parent() const { return *m_parent; }
williamr@2: 
williamr@2:     bool is_root() const { return m_parent == 0; }
williamr@2: 
williamr@2:     // Return the root graph of the subgraph tree.
williamr@2:     subgraph& root() {
williamr@2:       if (this->is_root())
williamr@2:         return *this;
williamr@2:       else
williamr@2:         return m_parent->root();
williamr@2:     }
williamr@2:     const subgraph& root() const {
williamr@2:       if (this->is_root())
williamr@2:         return *this;
williamr@2:       else
williamr@2:         return m_parent->root();
williamr@2:     }
williamr@2: 
williamr@2:     // Return the children subgraphs of this graph/subgraph.
williamr@2:     // Use a list of pointers because the VC++ std::list doesn't like
williamr@2:     // storing incomplete type.
williamr@2:     typedef indirect_iterator<
williamr@2:         typename ChildrenList::const_iterator
williamr@2:       , subgraph<Graph>
williamr@2:       , std::bidirectional_iterator_tag
williamr@2:     >
williamr@2:     children_iterator;
williamr@2: 
williamr@2:     typedef indirect_iterator<
williamr@2:         typename ChildrenList::const_iterator
williamr@2:       , subgraph<Graph> const
williamr@2:       , std::bidirectional_iterator_tag
williamr@2:     >
williamr@2:     const_children_iterator;
williamr@2: 
williamr@2:     std::pair<const_children_iterator, const_children_iterator>
williamr@2:     children() const
williamr@2:     {
williamr@2:       return std::make_pair(const_children_iterator(m_children.begin()),
williamr@2:                             const_children_iterator(m_children.end()));
williamr@2:     }
williamr@2: 
williamr@2:     std::pair<children_iterator, children_iterator>
williamr@2:     children()
williamr@2:     {
williamr@2:       return std::make_pair(children_iterator(m_children.begin()),
williamr@2:                             children_iterator(m_children.end()));
williamr@2:     }
williamr@2: 
williamr@2:     std::size_t num_children() const { return m_children.size(); }
williamr@2: 
williamr@2: #ifndef BOOST_GRAPH_NO_BUNDLED_PROPERTIES
williamr@2:     // Bundled properties support
williamr@2:     template<typename Descriptor>
williamr@2:     typename graph::detail::bundled_result<Graph, Descriptor>::type&
williamr@2:     operator[](Descriptor x)
williamr@2:     { 
williamr@2:       if (m_parent == 0) return m_graph[x];
williamr@2:       else return root().m_graph[local_to_global(x)];
williamr@2:     }
williamr@2: 
williamr@2:     template<typename Descriptor>
williamr@2:     typename graph::detail::bundled_result<Graph, Descriptor>::type const&
williamr@2:     operator[](Descriptor x) const
williamr@2:     { 
williamr@2:       if (m_parent == 0) return m_graph[x];
williamr@2:       else return root().m_graph[local_to_global(x)];
williamr@2:     }
williamr@2: #endif // BOOST_GRAPH_NO_BUNDLED_PROPERTIES
williamr@2: 
williamr@2:     //  private:
williamr@2:     typedef typename property_map<Graph, edge_index_t>::type EdgeIndexMap;
williamr@2:     typedef typename property_traits<EdgeIndexMap>::value_type edge_index_type;
williamr@2:     BOOST_STATIC_ASSERT((!is_same<edge_index_type, 
williamr@2:                         boost::detail::error_property_not_found>::value));
williamr@2: 
williamr@2:     Graph m_graph;
williamr@2:     subgraph<Graph>* m_parent;
williamr@2:     edge_index_type m_edge_counter; // for generating unique edge indices
williamr@2:     ChildrenList m_children;
williamr@2:     std::vector<vertex_descriptor> m_global_vertex; // local -> global
williamr@2:     std::map<vertex_descriptor, vertex_descriptor> m_local_vertex;  // global -> local
williamr@2:     std::vector<edge_descriptor> m_global_edge;              // local -> global
williamr@2:     std::map<edge_index_type, edge_descriptor> m_local_edge; // global -> local
williamr@2: 
williamr@2:     edge_descriptor
williamr@2:     local_add_edge(vertex_descriptor u_local, vertex_descriptor v_local,
williamr@2:                    edge_descriptor e_global)
williamr@2:     {
williamr@2:       edge_descriptor e_local;
williamr@2:       bool inserted;
williamr@2:       tie(e_local, inserted) = add_edge(u_local, v_local, m_graph);
williamr@2:       put(edge_index, m_graph, e_local, m_edge_counter++);
williamr@2:       m_global_edge.push_back(e_global);
williamr@2:       m_local_edge[get(get(edge_index, this->root()), e_global)] = e_local;
williamr@2:       return e_local;
williamr@2:     }
williamr@2: 
williamr@2:   };
williamr@2: 
williamr@2: #ifndef BOOST_GRAPH_NO_BUNDLED_PROPERTIES
williamr@2:   template<typename Graph>
williamr@2:   struct vertex_bundle_type<subgraph<Graph> > : vertex_bundle_type<Graph> { };
williamr@2: 
williamr@2:   template<typename Graph>
williamr@2:   struct edge_bundle_type<subgraph<Graph> > : edge_bundle_type<Graph> { };
williamr@2: #endif // BOOST_GRAPH_NO_BUNDLED_PROPERTIES
williamr@2: 
williamr@2:   //===========================================================================
williamr@2:   // Functions special to the Subgraph Class
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   typename subgraph<G>::vertex_descriptor
williamr@2:   add_vertex(typename subgraph<G>::vertex_descriptor u_global,
williamr@2:              subgraph<G>& g)
williamr@2:   {
williamr@2:     assert(!g.is_root());
williamr@2:     typename subgraph<G>::vertex_descriptor u_local, v_global, uu_global;
williamr@2:     typename subgraph<G>::edge_descriptor e_global;
williamr@2: 
williamr@2:     u_local = add_vertex(g.m_graph);
williamr@2:     g.m_global_vertex.push_back(u_global);
williamr@2:     g.m_local_vertex[u_global] = u_local;
williamr@2: 
williamr@2:     subgraph<G>& r = g.root();
williamr@2: 
williamr@2:     // remember edge global and local maps
williamr@2:     {
williamr@2:       typename subgraph<G>::out_edge_iterator ei, ei_end;
williamr@2:       for (tie(ei, ei_end) = out_edges(u_global, r);
williamr@2:            ei != ei_end; ++ei) {
williamr@2:         e_global = *ei;
williamr@2:         v_global = target(e_global, r);
williamr@2:         if (g.find_vertex(v_global).second == true)
williamr@2:           g.local_add_edge(u_local, g.global_to_local(v_global), e_global);
williamr@2:       }
williamr@2:     }
williamr@2:     if (is_directed(g)) { // not necessary for undirected graph
williamr@2:       typename subgraph<G>::vertex_iterator vi, vi_end;
williamr@2:       typename subgraph<G>::out_edge_iterator ei, ei_end;
williamr@2:       for (tie(vi, vi_end) = vertices(r); vi != vi_end; ++vi) {
williamr@2:         v_global = *vi;
williamr@2:         if (g.find_vertex(v_global).second)
williamr@2:           for (tie(ei, ei_end) = out_edges(*vi, r); ei != ei_end; ++ei) {
williamr@2:             e_global = *ei;
williamr@2:             uu_global = target(e_global, r);
williamr@2:             if (uu_global == u_global && g.find_vertex(v_global).second)
williamr@2:               g.local_add_edge(g.global_to_local(v_global), u_local, e_global);
williamr@2:           }
williamr@2:       }
williamr@2:     }
williamr@2: 
williamr@2:     return u_local;
williamr@2:   }
williamr@2: 
williamr@2:   //===========================================================================
williamr@2:   // Functions required by the IncidenceGraph concept
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   std::pair<typename graph_traits<G>::out_edge_iterator,
williamr@2:             typename graph_traits<G>::out_edge_iterator>
williamr@2:   out_edges(typename graph_traits<G>::vertex_descriptor u_local,
williamr@2:             const subgraph<G>& g)
williamr@2:     { return out_edges(u_local, g.m_graph); }
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   typename graph_traits<G>::degree_size_type
williamr@2:   out_degree(typename graph_traits<G>::vertex_descriptor u_local,
williamr@2:              const subgraph<G>& g)
williamr@2:     { return out_degree(u_local, g.m_graph); }
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   typename graph_traits<G>::vertex_descriptor
williamr@2:   source(typename graph_traits<G>::edge_descriptor e_local,
williamr@2:          const subgraph<G>& g)
williamr@2:     { return source(e_local, g.m_graph); }
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   typename graph_traits<G>::vertex_descriptor
williamr@2:   target(typename graph_traits<G>::edge_descriptor e_local,
williamr@2:          const subgraph<G>& g)
williamr@2:     { return target(e_local, g.m_graph); }
williamr@2: 
williamr@2:   //===========================================================================
williamr@2:   // Functions required by the BidirectionalGraph concept
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   std::pair<typename graph_traits<G>::in_edge_iterator,
williamr@2:             typename graph_traits<G>::in_edge_iterator>
williamr@2:   in_edges(typename graph_traits<G>::vertex_descriptor u_local,
williamr@2:             const subgraph<G>& g)
williamr@2:     { return in_edges(u_local, g.m_graph); }
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   typename graph_traits<G>::degree_size_type
williamr@2:   in_degree(typename graph_traits<G>::vertex_descriptor u_local,
williamr@2:              const subgraph<G>& g)
williamr@2:     { return in_degree(u_local, g.m_graph); }
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   typename graph_traits<G>::degree_size_type
williamr@2:   degree(typename graph_traits<G>::vertex_descriptor u_local,
williamr@2:              const subgraph<G>& g)
williamr@2:     { return degree(u_local, g.m_graph); }
williamr@2: 
williamr@2:   //===========================================================================
williamr@2:   // Functions required by the AdjacencyGraph concept
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   std::pair<typename subgraph<G>::adjacency_iterator,
williamr@2:             typename subgraph<G>::adjacency_iterator>
williamr@2:   adjacent_vertices(typename subgraph<G>::vertex_descriptor u_local,
williamr@2:                     const subgraph<G>& g)
williamr@2:     { return adjacent_vertices(u_local, g.m_graph); }
williamr@2: 
williamr@2:   //===========================================================================
williamr@2:   // Functions required by the VertexListGraph concept
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   std::pair<typename subgraph<G>::vertex_iterator,
williamr@2:             typename subgraph<G>::vertex_iterator>
williamr@2:   vertices(const subgraph<G>& g)
williamr@2:     { return vertices(g.m_graph); }
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   typename subgraph<G>::vertices_size_type
williamr@2:   num_vertices(const subgraph<G>& g)
williamr@2:     { return num_vertices(g.m_graph); }
williamr@2: 
williamr@2:   //===========================================================================
williamr@2:   // Functions required by the EdgeListGraph concept
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   std::pair<typename subgraph<G>::edge_iterator,
williamr@2:             typename subgraph<G>::edge_iterator>
williamr@2:   edges(const subgraph<G>& g)
williamr@2:     { return edges(g.m_graph); }
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   typename subgraph<G>::edges_size_type
williamr@2:   num_edges(const subgraph<G>& g)
williamr@2:     { return num_edges(g.m_graph); }
williamr@2: 
williamr@2:   //===========================================================================
williamr@2:   // Functions required by the AdjacencyMatrix concept
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   std::pair<typename subgraph<G>::edge_descriptor, bool>
williamr@2:   edge(typename subgraph<G>::vertex_descriptor u_local,
williamr@2:        typename subgraph<G>::vertex_descriptor v_local,
williamr@2:        const subgraph<G>& g)
williamr@2:   {
williamr@2:     return edge(u_local, v_local, g.m_graph);
williamr@2:   }
williamr@2: 
williamr@2:   //===========================================================================
williamr@2:   // Functions required by the MutableGraph concept
williamr@2: 
williamr@2:   namespace detail {
williamr@2: 
williamr@2:     template <typename Vertex, typename Edge, typename Graph>
williamr@2:     void add_edge_recur_down
williamr@2:     (Vertex u_global, Vertex v_global, Edge e_global, subgraph<Graph>& g);
williamr@2: 
williamr@2:     template <typename Vertex, typename Edge, typename Children, typename G>
williamr@2:     void children_add_edge(Vertex u_global, Vertex v_global, Edge e_global,
williamr@2:                            Children& c, subgraph<G>* orig)
williamr@2:     {
williamr@2:       for (typename Children::iterator i = c.begin(); i != c.end(); ++i)
williamr@2:         if ((*i)->find_vertex(u_global).second
williamr@2:             && (*i)->find_vertex(v_global).second)
williamr@2:           add_edge_recur_down(u_global, v_global, e_global, **i, orig);
williamr@2:     }
williamr@2: 
williamr@2:     template <typename Vertex, typename Edge, typename Graph>
williamr@2:     void add_edge_recur_down
williamr@2:       (Vertex u_global, Vertex v_global, Edge e_global, subgraph<Graph>& g,
williamr@2:        subgraph<Graph>* orig)
williamr@2:     {
williamr@2:       if (&g != orig ) {
williamr@2:         // add local edge only if u_global and v_global are in subgraph g
williamr@2:         Vertex u_local, v_local;
williamr@2:         bool u_in_subgraph, v_in_subgraph;
williamr@2:         tie(u_local, u_in_subgraph) = g.find_vertex(u_global);
williamr@2:         tie(v_local, v_in_subgraph) = g.find_vertex(v_global);
williamr@2:         if (u_in_subgraph && v_in_subgraph)
williamr@2:           g.local_add_edge(u_local, v_local, e_global);
williamr@2:       }
williamr@2:       children_add_edge(u_global, v_global, e_global, g.m_children, orig);
williamr@2:     }
williamr@2: 
williamr@2:     template <typename Vertex, typename Graph>
williamr@2:     std::pair<typename subgraph<Graph>::edge_descriptor, bool>
williamr@2:     add_edge_recur_up(Vertex u_global, Vertex v_global,
williamr@2:                       const typename Graph::edge_property_type& ep,
williamr@2:                       subgraph<Graph>& g, subgraph<Graph>* orig)
williamr@2:     {
williamr@2:       if (g.is_root()) {
williamr@2:         typename subgraph<Graph>::edge_descriptor e_global;
williamr@2:         bool inserted;
williamr@2:         tie(e_global, inserted) = add_edge(u_global, v_global, ep, g.m_graph);
williamr@2:         put(edge_index, g.m_graph, e_global, g.m_edge_counter++);
williamr@2:         g.m_global_edge.push_back(e_global);
williamr@2:         children_add_edge(u_global, v_global, e_global, g.m_children, orig);
williamr@2:         return std::make_pair(e_global, inserted);
williamr@2:       } else
williamr@2:         return add_edge_recur_up(u_global, v_global, ep, *g.m_parent, orig);
williamr@2:     }
williamr@2: 
williamr@2:   } // namespace detail
williamr@2: 
williamr@2:   // Add an edge to the subgraph g, specified by the local vertex
williamr@2:   // descriptors u and v. In addition, the edge will be added to any
williamr@2:   // other subgraphs which contain vertex descriptors u and v.
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   std::pair<typename subgraph<G>::edge_descriptor, bool>
williamr@2:   add_edge(typename subgraph<G>::vertex_descriptor u_local,
williamr@2:            typename subgraph<G>::vertex_descriptor v_local,
williamr@2:            const typename G::edge_property_type& ep,
williamr@2:            subgraph<G>& g)
williamr@2:   {
williamr@2:     if (g.is_root()) // u_local and v_local are really global
williamr@2:       return detail::add_edge_recur_up(u_local, v_local, ep, g, &g);
williamr@2:     else {
williamr@2:       typename subgraph<G>::edge_descriptor e_local, e_global;
williamr@2:       bool inserted;
williamr@2:       tie(e_global, inserted) = detail::add_edge_recur_up
williamr@2:         (g.local_to_global(u_local), g.local_to_global(v_local), ep, g, &g);
williamr@2:       e_local = g.local_add_edge(u_local, v_local, e_global);
williamr@2:       return std::make_pair(e_local, inserted);
williamr@2:     }
williamr@2:   }
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   std::pair<typename subgraph<G>::edge_descriptor, bool>
williamr@2:   add_edge(typename subgraph<G>::vertex_descriptor u,
williamr@2:            typename subgraph<G>::vertex_descriptor v,
williamr@2:            subgraph<G>& g)
williamr@2:   {
williamr@2:     typename G::edge_property_type ep;
williamr@2:     return add_edge(u, v, ep, g);
williamr@2:   }
williamr@2: 
williamr@2:   namespace detail {
williamr@2: 
williamr@2:     //-------------------------------------------------------------------------
williamr@2:     // implementation of remove_edge(u,v,g)
williamr@2: 
williamr@2:     template <typename Vertex, typename Graph>
williamr@2:     void remove_edge_recur_down(Vertex u_global, Vertex v_global,
williamr@2:                                 subgraph<Graph>& g);
williamr@2: 
williamr@2:     template <typename Vertex, typename Children>
williamr@2:     void children_remove_edge(Vertex u_global, Vertex v_global,
williamr@2:                               Children& c)
williamr@2:     {
williamr@2:       for (typename Children::iterator i = c.begin(); i != c.end(); ++i)
williamr@2:         if ((*i)->find_vertex(u_global).second
williamr@2:             && (*i)->find_vertex(v_global).second)
williamr@2:           remove_edge_recur_down(u_global, v_global, **i);
williamr@2:     }
williamr@2: 
williamr@2:     template <typename Vertex, typename Graph>
williamr@2:     void remove_edge_recur_down(Vertex u_global, Vertex v_global,
williamr@2:                                 subgraph<Graph>& g)
williamr@2:     {
williamr@2:       Vertex u_local, v_local;
williamr@2:       u_local = g.m_local_vertex[u_global];
williamr@2:       v_local = g.m_local_vertex[v_global];
williamr@2:       remove_edge(u_local, v_local, g.m_graph);
williamr@2:       children_remove_edge(u_global, v_global, g.m_children);
williamr@2:     }
williamr@2: 
williamr@2:     template <typename Vertex, typename Graph>
williamr@2:     void remove_edge_recur_up(Vertex u_global, Vertex v_global,
williamr@2:                               subgraph<Graph>& g)
williamr@2:     {
williamr@2:       if (g.is_root()) {
williamr@2:         remove_edge(u_global, v_global, g.m_graph);
williamr@2:         children_remove_edge(u_global, v_global, g.m_children);
williamr@2:       } else
williamr@2:         remove_edge_recur_up(u_global, v_global, *g.m_parent);
williamr@2:     }
williamr@2: 
williamr@2:     //-------------------------------------------------------------------------
williamr@2:     // implementation of remove_edge(e,g)
williamr@2: 
williamr@2:     template <typename Edge, typename Graph>
williamr@2:     void remove_edge_recur_down(Edge e_global, subgraph<Graph>& g);
williamr@2: 
williamr@2:     template <typename Edge, typename Children>
williamr@2:     void children_remove_edge(Edge e_global, Children& c)
williamr@2:     {
williamr@2:       for (typename Children::iterator i = c.begin(); i != c.end(); ++i)
williamr@2:         if ((*i)->find_vertex(source(e_global, **i)).second
williamr@2:             && (*i)->find_vertex(target(e_global, **i)).second)
williamr@2:           remove_edge_recur_down(source(e_global, **i),
williamr@2:                                  target(e_global, **i), **i);
williamr@2:     }
williamr@2: 
williamr@2:     template <typename Edge, typename Graph>
williamr@2:     void remove_edge_recur_down(Edge e_global, subgraph<Graph>& g)
williamr@2:     {
williamr@2:       remove_edge(g.global_to_local(e_global), g.m_graph);
williamr@2:       children_remove_edge(e_global, g.m_children);
williamr@2:     }
williamr@2: 
williamr@2:     template <typename Edge, typename Graph>
williamr@2:     void remove_edge_recur_up(Edge e_global, subgraph<Graph>& g)
williamr@2:     {
williamr@2:       if (g.is_root()) {
williamr@2:         remove_edge(e_global, g.m_graph);
williamr@2:         children_remove_edge(e_global, g.m_children);
williamr@2:       } else
williamr@2:         remove_edge_recur_up(e_global, *g.m_parent);
williamr@2:     }
williamr@2: 
williamr@2:   } // namespace detail
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   void
williamr@2:   remove_edge(typename subgraph<G>::vertex_descriptor u_local,
williamr@2:               typename subgraph<G>::vertex_descriptor v_local,
williamr@2:               subgraph<G>& g)
williamr@2:   {
williamr@2:     if (g.is_root())
williamr@2:       detail::remove_edge_recur_up(u_local, v_local, g);
williamr@2:     else
williamr@2:       detail::remove_edge_recur_up(g.local_to_global(u_local),
williamr@2:                                    g.local_to_global(v_local), g);
williamr@2:   }
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   void
williamr@2:   remove_edge(typename subgraph<G>::edge_descriptor e_local,
williamr@2:               subgraph<G>& g)
williamr@2:   {
williamr@2:     if (g.is_root())
williamr@2:       detail::remove_edge_recur_up(e_local, g);
williamr@2:     else
williamr@2:       detail::remove_edge_recur_up(g.local_to_global(e_local), g);
williamr@2:   }
williamr@2: 
williamr@2:   template <typename Predicate, typename G>
williamr@2:   void
williamr@2:   remove_edge_if(Predicate p, subgraph<G>& g)
williamr@2:   {
williamr@2:     // This is wrong...
williamr@2:     remove_edge_if(p, g.m_graph);
williamr@2:   }
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   void
williamr@2:   clear_vertex(typename subgraph<G>::vertex_descriptor v_local,
williamr@2:                subgraph<G>& g)
williamr@2:   {
williamr@2:     // this is wrong...
williamr@2:     clear_vertex(v_local, g.m_graph);
williamr@2:   }
williamr@2: 
williamr@2:   namespace detail {
williamr@2: 
williamr@2:     template <typename G>
williamr@2:     typename subgraph<G>::vertex_descriptor
williamr@2:     add_vertex_recur_up(subgraph<G>& g)
williamr@2:     {
williamr@2:       typename subgraph<G>::vertex_descriptor u_local, u_global;
williamr@2:       if (g.is_root()) {
williamr@2:         u_global = add_vertex(g.m_graph);
williamr@2:         g.m_global_vertex.push_back(u_global);
williamr@2:       } else {
williamr@2:         u_global = add_vertex_recur_up(*g.m_parent);
williamr@2:         u_local = add_vertex(g.m_graph);
williamr@2:         g.m_global_vertex.push_back(u_global);
williamr@2:         g.m_local_vertex[u_global] = u_local;
williamr@2:       }
williamr@2:       return u_global;
williamr@2:     }
williamr@2: 
williamr@2:   } // namespace detail
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   typename subgraph<G>::vertex_descriptor
williamr@2:   add_vertex(subgraph<G>& g)
williamr@2:   {
williamr@2:     typename subgraph<G>::vertex_descriptor  u_local, u_global;
williamr@2:     if (g.is_root()) {
williamr@2:       u_global = add_vertex(g.m_graph);
williamr@2:       g.m_global_vertex.push_back(u_global);
williamr@2:       u_local = u_global;
williamr@2:     } else {
williamr@2:       u_global = detail::add_vertex_recur_up(g.parent());
williamr@2:       u_local = add_vertex(g.m_graph);
williamr@2:       g.m_global_vertex.push_back(u_global);
williamr@2:       g.m_local_vertex[u_global] = u_local;
williamr@2:     }
williamr@2:     return u_local;
williamr@2:   }
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   void remove_vertex(typename subgraph<G>::vertex_descriptor u,
williamr@2:                      subgraph<G>& g)
williamr@2:   {
williamr@2:     // UNDER CONSTRUCTION
williamr@2:     assert(false);
williamr@2:   }
williamr@2: 
williamr@2: 
williamr@2:   //===========================================================================
williamr@2:   // Functions required by the PropertyGraph concept
williamr@2: 
williamr@2:   template <typename GraphPtr, typename PropertyMap, typename Tag>
williamr@2:   class subgraph_global_property_map
williamr@2:     : public put_get_helper<
williamr@2:         typename property_traits<PropertyMap>::reference,
williamr@2:         subgraph_global_property_map<GraphPtr, PropertyMap, Tag> >
williamr@2:   {
williamr@2:     typedef property_traits<PropertyMap> Traits;
williamr@2:   public:
williamr@2:     typedef typename Traits::category category;
williamr@2:     typedef typename Traits::value_type value_type;
williamr@2:     typedef typename Traits::key_type key_type;
williamr@2:     typedef typename Traits::reference reference;
williamr@2: 
williamr@2:     subgraph_global_property_map() { }
williamr@2: 
williamr@2:     subgraph_global_property_map(GraphPtr g)
williamr@2:       : m_g(g) { }
williamr@2: 
williamr@2:     inline reference operator[](key_type e_local) const {
williamr@2:       PropertyMap pmap = get(Tag(), m_g->root().m_graph);
williamr@2:       if (m_g->m_parent == 0)
williamr@2:         return pmap[e_local];
williamr@2:       else
williamr@2:         return pmap[m_g->local_to_global(e_local)];
williamr@2:     }
williamr@2:     GraphPtr m_g;
williamr@2:   };
williamr@2: 
williamr@2:   template <typename GraphPtr, typename PropertyMap, typename Tag>
williamr@2:   class subgraph_local_property_map
williamr@2:     : public put_get_helper<
williamr@2:         typename property_traits<PropertyMap>::reference,
williamr@2:         subgraph_local_property_map<GraphPtr, PropertyMap, Tag> >
williamr@2:   {
williamr@2:     typedef property_traits<PropertyMap> Traits;
williamr@2:   public:
williamr@2:     typedef typename Traits::category category;
williamr@2:     typedef typename Traits::value_type value_type;
williamr@2:     typedef typename Traits::key_type key_type;
williamr@2:     typedef typename Traits::reference reference;
williamr@2: 
williamr@2:     subgraph_local_property_map() { }
williamr@2: 
williamr@2:     subgraph_local_property_map(GraphPtr g)
williamr@2:       : m_g(g) { }
williamr@2: 
williamr@2:     inline reference operator[](key_type e_local) const {
williamr@2:       PropertyMap pmap = get(Tag(), *m_g);
williamr@2:       return pmap[e_local];
williamr@2:     }
williamr@2:     GraphPtr m_g;
williamr@2:   };
williamr@2: 
williamr@2:   namespace detail {
williamr@2: 
williamr@2:     struct subgraph_any_pmap {
williamr@2:       template <class Tag, class SubGraph, class Property>
williamr@2:       class bind_ {
williamr@2:         typedef typename SubGraph::graph_type Graph;
williamr@2:         typedef SubGraph* SubGraphPtr;
williamr@2:         typedef const SubGraph* const_SubGraphPtr;
williamr@2:         typedef typename property_map<Graph, Tag>::type PMap;
williamr@2:         typedef typename property_map<Graph, Tag>::const_type const_PMap;
williamr@2:       public:
williamr@2:         typedef subgraph_global_property_map<SubGraphPtr, PMap, Tag> type;
williamr@2:         typedef subgraph_global_property_map<const_SubGraphPtr, const_PMap, Tag>
williamr@2:           const_type;
williamr@2:       };
williamr@2:     };
williamr@2:     struct subgraph_id_pmap {
williamr@2:       template <class Tag, class SubGraph, class Property>
williamr@2:       struct bind_ {
williamr@2:         typedef typename SubGraph::graph_type Graph;
williamr@2:         typedef SubGraph* SubGraphPtr;
williamr@2:         typedef const SubGraph* const_SubGraphPtr;
williamr@2:         typedef typename property_map<Graph, Tag>::type PMap;
williamr@2:         typedef typename property_map<Graph, Tag>::const_type const_PMap;
williamr@2:       public:
williamr@2:         typedef subgraph_local_property_map<SubGraphPtr, PMap, Tag> type;
williamr@2:         typedef subgraph_local_property_map<const_SubGraphPtr, const_PMap, Tag>
williamr@2:           const_type;
williamr@2:       };
williamr@2:     };
williamr@2:     template <class Tag>
williamr@2:     struct subgraph_choose_pmap_helper {
williamr@2:       typedef subgraph_any_pmap type;
williamr@2:     };
williamr@2:     template <>
williamr@2:     struct subgraph_choose_pmap_helper<vertex_index_t> {
williamr@2:       typedef subgraph_id_pmap type;
williamr@2:     };
williamr@2:     template <class Tag, class Graph, class Property>
williamr@2:     struct subgraph_choose_pmap {
williamr@2:       typedef typename subgraph_choose_pmap_helper<Tag>::type Helper;
williamr@2:       typedef typename Helper::template bind_<Tag, Graph, Property> Bind;
williamr@2:       typedef typename Bind::type type;
williamr@2:       typedef typename Bind::const_type const_type;
williamr@2:     };
williamr@2:     struct subgraph_property_generator {
williamr@2:       template <class SubGraph, class Property, class Tag>
williamr@2:       struct bind_ {
williamr@2:         typedef subgraph_choose_pmap<Tag, SubGraph, Property> Choice;
williamr@2:         typedef typename Choice::type type;
williamr@2:         typedef typename Choice::const_type const_type;
williamr@2:       };
williamr@2:     };
williamr@2: 
williamr@2:   } // namespace detail
williamr@2: 
williamr@2:   template <>
williamr@2:   struct vertex_property_selector<subgraph_tag> {
williamr@2:     typedef detail::subgraph_property_generator type;
williamr@2:   };
williamr@2: 
williamr@2:   template <>
williamr@2:   struct edge_property_selector<subgraph_tag> {
williamr@2:     typedef detail::subgraph_property_generator type;
williamr@2:   };
williamr@2: 
williamr@2:   template <typename G, typename Property>
williamr@2:   typename property_map< subgraph<G>, Property>::type
williamr@2:   get(Property, subgraph<G>& g)
williamr@2:   {
williamr@2:     typedef typename property_map< subgraph<G>, Property>::type PMap;
williamr@2:     return PMap(&g);
williamr@2:   }
williamr@2: 
williamr@2:   template <typename G, typename Property>
williamr@2:   typename property_map< subgraph<G>, Property>::const_type
williamr@2:   get(Property, const subgraph<G>& g)
williamr@2:   {
williamr@2:     typedef typename property_map< subgraph<G>, Property>::const_type PMap;
williamr@2:     return PMap(&g);
williamr@2:   }
williamr@2: 
williamr@2:   template <typename G, typename Property, typename Key>
williamr@2:   typename property_traits<
williamr@2:     typename property_map< subgraph<G>, Property>::const_type
williamr@2:   >::value_type
williamr@2:   get(Property, const subgraph<G>& g, const Key& k)
williamr@2:   {
williamr@2:     typedef typename property_map< subgraph<G>, Property>::const_type PMap;
williamr@2:     PMap pmap(&g);
williamr@2:     return pmap[k];
williamr@2:   }
williamr@2: 
williamr@2:   template <typename G, typename Property, typename Key, typename Value>
williamr@2:   void
williamr@2:   put(Property, subgraph<G>& g, const Key& k, const Value& val)
williamr@2:   {
williamr@2:     typedef typename property_map< subgraph<G>, Property>::type PMap;
williamr@2:     PMap pmap(&g);
williamr@2:     pmap[k] = val;
williamr@2:   }
williamr@2: 
williamr@2:   template <typename G, typename Tag>
williamr@2:   inline
williamr@2:   typename graph_property<G, Tag>::type&
williamr@2:   get_property(subgraph<G>& g, Tag tag) {
williamr@2:     return get_property(g.m_graph, tag);
williamr@2:   }
williamr@2: 
williamr@2:   template <typename G, typename Tag>
williamr@2:   inline
williamr@2:   const typename graph_property<G, Tag>::type&
williamr@2:   get_property(const subgraph<G>& g, Tag tag) {
williamr@2:     return get_property(g.m_graph, tag);
williamr@2:   }
williamr@2: 
williamr@2:   //===========================================================================
williamr@2:   // Miscellaneous Functions
williamr@2: 
williamr@2:   template <typename G>
williamr@2:   typename subgraph<G>::vertex_descriptor
williamr@2:   vertex(typename subgraph<G>::vertices_size_type n, const subgraph<G>& g)
williamr@2:   {
williamr@2:     return vertex(n, g.m_graph);
williamr@2:   }
williamr@2: 
williamr@2: } // namespace boost
williamr@2: 
williamr@2: #endif // BOOST_SUBGRAPH_HPP