Added boost header

test/external/boost/graph/strong_components.hpp

@@ -0,0 +1,341 @@
+//
+//=======================================================================
+// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
+// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
+//
+// Distributed under the Boost Software License, Version 1.0. (See
+// accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//=======================================================================
+//
+
+#ifndef BOOST_GRAPH_STRONG_COMPONENTS_HPP
+#define BOOST_GRAPH_STRONG_COMPONENTS_HPP
+
+#include <stack>
+#include <boost/config.hpp>
+#include <boost/graph/depth_first_search.hpp>
+#include <boost/type_traits/conversion_traits.hpp>
+#include <boost/static_assert.hpp>
+#include <boost/graph/overloading.hpp>
+
+namespace boost {
+
+  //==========================================================================
+  // This is Tarjan's algorithm for strongly connected components
+  // from his paper "Depth first search and linear graph algorithms".
+  // It calculates the components in a single application of DFS.
+  // We implement the algorithm as a dfs-visitor.
+
+  namespace detail {
+    
+    template <typename ComponentMap, typename RootMap, typename DiscoverTime,
+              typename Stack>
+    class tarjan_scc_visitor : public dfs_visitor<> 
+    {
+      typedef typename property_traits<ComponentMap>::value_type comp_type;
+      typedef typename property_traits<DiscoverTime>::value_type time_type;
+    public:
+      tarjan_scc_visitor(ComponentMap comp_map, RootMap r, DiscoverTime d, 
+                         comp_type& c_, Stack& s_)
+        : c(c_), comp(comp_map), root(r), discover_time(d),
+          dfs_time(time_type()), s(s_) { }
+
+      template <typename Graph>
+      void discover_vertex(typename graph_traits<Graph>::vertex_descriptor v,
+                           const Graph&) {
+        put(root, v, v);
+        put(comp, v, (std::numeric_limits<comp_type>::max)());
+        put(discover_time, v, dfs_time++);
+        s.push(v);
+      }
+      template <typename Graph>
+      void finish_vertex(typename graph_traits<Graph>::vertex_descriptor v,
+                         const Graph& g) {
+        typename graph_traits<Graph>::vertex_descriptor w;
+        typename graph_traits<Graph>::out_edge_iterator ei, ei_end;
+        for (boost::tie(ei, ei_end) = out_edges(v, g); ei != ei_end; ++ei) {
+          w = target(*ei, g);
+          if (get(comp, w) == (std::numeric_limits<comp_type>::max)())
+            put(root, v, this->min_discover_time(get(root,v), get(root,w)));
+        }
+        if (get(root, v) == v) {
+          do {
+            w = s.top(); s.pop();
+            put(comp, w, c);
+          } while (w != v);
+          ++c;
+        }
+      }
+    private:
+      template <typename Vertex>
+      Vertex min_discover_time(Vertex u, Vertex v) {
+        return get(discover_time, u) < get(discover_time,v) ? u : v;
+      }
+
+      comp_type& c;
+      ComponentMap comp;
+      RootMap root;
+      DiscoverTime discover_time;
+      time_type dfs_time;
+      Stack& s;
+    };
+    
+    template <class Graph, class ComponentMap, class RootMap,
+              class DiscoverTime, class P, class T, class R>
+    typename property_traits<ComponentMap>::value_type
+    strong_components_impl
+      (const Graph& g,    // Input
+       ComponentMap comp, // Output
+       // Internal record keeping
+       RootMap root, 
+       DiscoverTime discover_time,
+       const bgl_named_params<P, T, R>& params)
+    {
+      typedef typename graph_traits<Graph>::vertex_descriptor Vertex;
+      function_requires< ReadWritePropertyMapConcept<ComponentMap, Vertex> >();
+      function_requires< ReadWritePropertyMapConcept<RootMap, Vertex> >();
+      typedef typename property_traits<RootMap>::value_type RootV;
+      function_requires< ConvertibleConcept<RootV, Vertex> >();
+      function_requires< ReadWritePropertyMapConcept<DiscoverTime, Vertex> >();
+
+      typename property_traits<ComponentMap>::value_type total = 0;
+
+      std::stack<Vertex> s;
+      detail::tarjan_scc_visitor<ComponentMap, RootMap, DiscoverTime, 
+        std::stack<Vertex> > 
+        vis(comp, root, discover_time, total, s);
+      depth_first_search(g, params.visitor(vis));
+      return total;
+    }
+
+    //-------------------------------------------------------------------------
+    // The dispatch functions handle the defaults for the rank and discover
+    // time property maps.
+    // dispatch with class specialization to avoid VC++ bug
+
+    template <class DiscoverTimeMap>
+    struct strong_comp_dispatch2 {
+      template <class Graph, class ComponentMap, class RootMap, class P, class T, class R>
+      inline static typename property_traits<ComponentMap>::value_type
+      apply(const Graph& g,
+            ComponentMap comp,
+            RootMap r_map,
+            const bgl_named_params<P, T, R>& params,
+            DiscoverTimeMap time_map)
+      {
+        return strong_components_impl(g, comp, r_map, time_map, params);
+      }
+    };
+
+
+    template <>
+    struct strong_comp_dispatch2<detail::error_property_not_found> {
+      template <class Graph, class ComponentMap, class RootMap,
+                class P, class T, class R>
+      inline static typename property_traits<ComponentMap>::value_type
+      apply(const Graph& g,
+            ComponentMap comp,
+            RootMap r_map,
+            const bgl_named_params<P, T, R>& params,
+            detail::error_property_not_found)
+      {
+        typedef typename graph_traits<Graph>::vertices_size_type size_type;
+        size_type       n = num_vertices(g) > 0 ? num_vertices(g) : 1;
+        std::vector<size_type> time_vec(n);
+        return strong_components_impl
+          (g, comp, r_map,
+           make_iterator_property_map(time_vec.begin(), choose_const_pmap
+                                      (get_param(params, vertex_index),
+                                       g, vertex_index), time_vec[0]),
+           params);
+      }
+    };
+
+    template <class Graph, class ComponentMap, class RootMap,
+              class P, class T, class R, class DiscoverTimeMap>
+    inline typename property_traits<ComponentMap>::value_type
+    scc_helper2(const Graph& g,
+                ComponentMap comp,
+                RootMap r_map,
+                const bgl_named_params<P, T, R>& params,
+                DiscoverTimeMap time_map)
+    {
+      return strong_comp_dispatch2<DiscoverTimeMap>::apply(g, comp, r_map, params, time_map);
+    }
+
+    template <class RootMap>
+    struct strong_comp_dispatch1 {
+
+      template <class Graph, class ComponentMap, class P, class T, class R>
+      inline static typename property_traits<ComponentMap>::value_type
+      apply(const Graph& g,
+            ComponentMap comp,
+            const bgl_named_params<P, T, R>& params,
+            RootMap r_map)
+      {
+        return scc_helper2(g, comp, r_map, params, get_param(params, vertex_discover_time));
+      }
+    };
+    template <>
+    struct strong_comp_dispatch1<detail::error_property_not_found> {
+
+      template <class Graph, class ComponentMap, 
+                class P, class T, class R>
+      inline static typename property_traits<ComponentMap>::value_type
+      apply(const Graph& g,
+            ComponentMap comp,
+            const bgl_named_params<P, T, R>& params,
+            detail::error_property_not_found)
+      {
+        typedef typename graph_traits<Graph>::vertex_descriptor Vertex;
+        typename std::vector<Vertex>::size_type
+          n = num_vertices(g) > 0 ? num_vertices(g) : 1;
+        std::vector<Vertex> root_vec(n);
+        return scc_helper2
+          (g, comp, 
+           make_iterator_property_map(root_vec.begin(), choose_const_pmap
+                                      (get_param(params, vertex_index),
+                                       g, vertex_index), root_vec[0]),
+           params, 
+           get_param(params, vertex_discover_time));
+      }
+    };
+
+    template <class Graph, class ComponentMap, class RootMap,
+              class P, class T, class R>
+    inline typename property_traits<ComponentMap>::value_type
+    scc_helper1(const Graph& g,
+               ComponentMap comp,
+               const bgl_named_params<P, T, R>& params,
+               RootMap r_map)
+    {
+      return detail::strong_comp_dispatch1<RootMap>::apply(g, comp, params,
+                                                           r_map);
+    }
+
+  } // namespace detail 
+
+  template <class Graph, class ComponentMap, 
+            class P, class T, class R>
+  inline typename property_traits<ComponentMap>::value_type
+  strong_components(const Graph& g, ComponentMap comp,
+                    const bgl_named_params<P, T, R>& params
+                    BOOST_GRAPH_ENABLE_IF_MODELS_PARM(Graph, vertex_list_graph_tag))
+  {
+    typedef typename graph_traits<Graph>::directed_category DirCat;
+    BOOST_STATIC_ASSERT((is_convertible<DirCat*, directed_tag*>::value == true));
+    return detail::scc_helper1(g, comp, params, 
+                               get_param(params, vertex_root_t()));
+  }
+
+  template <class Graph, class ComponentMap>
+  inline typename property_traits<ComponentMap>::value_type
+  strong_components(const Graph& g, ComponentMap comp
+                    BOOST_GRAPH_ENABLE_IF_MODELS_PARM(Graph, vertex_list_graph_tag))
+  {
+    typedef typename graph_traits<Graph>::directed_category DirCat;
+    BOOST_STATIC_ASSERT((is_convertible<DirCat*, directed_tag*>::value == true));
+    bgl_named_params<int, int> params(0);
+    return strong_components(g, comp, params);
+  }
+
+  template <typename Graph, typename ComponentMap, typename ComponentLists>
+  void build_component_lists
+    (const Graph& g,
+     typename graph_traits<Graph>::vertices_size_type num_scc,
+     ComponentMap component_number,
+     ComponentLists& components)
+  {
+    components.resize(num_scc);
+    typename graph_traits<Graph>::vertex_iterator vi, vi_end;
+    for (boost::tie(vi, vi_end) = vertices(g); vi != vi_end; ++vi)
+      components[component_number[*vi]].push_back(*vi);
+  }
+
+
+} // namespace boost
+
+#include <queue>
+#include <vector>
+#include <boost/graph/transpose_graph.hpp>
+#include <boost/pending/indirect_cmp.hpp>
+#include <boost/graph/connected_components.hpp> // for components_recorder
+
+namespace boost {
+
+  //==========================================================================
+  // This is the version of strongly connected components from
+  // "Intro. to Algorithms" by Cormen, Leiserson, Rivest, which was
+  // adapted from "Data Structure and Algorithms" by Aho, Hopcroft,
+  // and Ullman, who credit the algorithm to S.R. Kosaraju and M. Sharir.
+  // The algorithm is based on computing DFS forests the graph
+  // and its transpose.
+
+  // This algorithm is slower than Tarjan's by a constant factor, uses
+  // more memory, and puts more requirements on the graph type.
+
+  template <class Graph, class DFSVisitor, class ComponentsMap,
+            class DiscoverTime, class FinishTime,
+            class ColorMap>
+  typename property_traits<ComponentsMap>::value_type
+  kosaraju_strong_components(Graph& G, ComponentsMap c,
+                             FinishTime finish_time, ColorMap color)
+  {
+    function_requires< MutableGraphConcept<Graph> >();
+    // ...
+    
+    typedef typename graph_traits<Graph>::vertex_descriptor Vertex;
+    typedef typename property_traits<ColorMap>::value_type ColorValue;
+    typedef color_traits<ColorValue> Color;
+    typename property_traits<FinishTime>::value_type time = 0;
+    depth_first_search
+     (G, make_dfs_visitor(stamp_times(finish_time, time, on_finish_vertex())),
+      color);
+
+    Graph G_T(num_vertices(G));
+    transpose_graph(G, G_T);
+
+    typedef typename property_traits<ComponentsMap>::value_type count_type;
+
+    count_type c_count(0);
+    detail::components_recorder<ComponentsMap>
+      vis(c, c_count);
+
+    // initialize G_T
+    typename graph_traits<Graph>::vertex_iterator ui, ui_end;
+    for (boost::tie(ui, ui_end) = vertices(G_T); ui != ui_end; ++ui)
+      put(color, *ui, Color::white());
+
+    typedef typename property_traits<FinishTime>::value_type D;
+    typedef indirect_cmp< FinishTime, std::less<D> > Compare;
+
+    Compare fl(finish_time);
+    std::priority_queue<Vertex, std::vector<Vertex>, Compare > Q(fl);
+
+    typename graph_traits<Graph>::vertex_iterator i, j, iend, jend;
+    boost::tie(i, iend) = vertices(G_T);
+    boost::tie(j, jend) = vertices(G);
+    for ( ; i != iend; ++i, ++j) {
+      put(finish_time, *i, get(finish_time, *j));
+       Q.push(*i);
+    }
+
+    while ( !Q.empty() ) {
+      Vertex u = Q.top();
+      Q.pop();
+      if  (get(color, u) == Color::white()) {
+        depth_first_visit(G_T, u, vis, color);
+        ++c_count; 
+      }
+    }
+    return c_count;
+  }
+
+} // namespace boost
+
+#ifdef BOOST_GRAPH_USE_MPI
+#  include <boost/graph/distributed/strong_components.hpp>
+#endif
+
+#endif // BOOST_GRAPH_STRONG_COMPONENTS_HPP