1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/epoc32/include/stdapis/boost/graph/topological_sort.hpp	Tue Mar 16 16:12:26 2010 +0000
     1.3 @@ -0,0 +1,76 @@
     1.4 +//
     1.5 +//=======================================================================
     1.6 +// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
     1.7 +// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
     1.8 +//
     1.9 +// Distributed under the Boost Software License, Version 1.0. (See
    1.10 +// accompanying file LICENSE_1_0.txt or copy at
    1.11 +// http://www.boost.org/LICENSE_1_0.txt)
    1.12 +//=======================================================================
    1.13 +//
    1.14 +#ifndef BOOST_GRAPH_TOPOLOGICAL_SORT_HPP
    1.15 +#define BOOST_GRAPH_TOPOLOGICAL_SORT_HPP
    1.16 +
    1.17 +#include <boost/config.hpp>
    1.18 +#include <boost/property_map.hpp>
    1.19 +#include <boost/graph/depth_first_search.hpp>
    1.20 +#include <boost/graph/visitors.hpp>
    1.21 +#include <boost/graph/exception.hpp>
    1.22 +
    1.23 +namespace boost { 
    1.24 +
    1.25 +
    1.26 +  // Topological sort visitor
    1.27 +  //
    1.28 +  // This visitor merely writes the linear ordering into an
    1.29 +  // OutputIterator. The OutputIterator could be something like an
    1.30 +  // ostream_iterator, or it could be a back/front_insert_iterator.
    1.31 +  // Note that if it is a back_insert_iterator, the recorded order is
    1.32 +  // the reverse topological order. On the other hand, if it is a
    1.33 +  // front_insert_iterator, the recorded order is the topological
    1.34 +  // order.
    1.35 +  //
    1.36 +  template <typename OutputIterator>
    1.37 +  struct topo_sort_visitor : public dfs_visitor<>
    1.38 +  {
    1.39 +    topo_sort_visitor(OutputIterator _iter)
    1.40 +      : m_iter(_iter) { }
    1.41 +    
    1.42 +    template <typename Edge, typename Graph>
    1.43 +    void back_edge(const Edge& u, Graph&) { throw not_a_dag(); }
    1.44 +    
    1.45 +    template <typename Vertex, typename Graph> 
    1.46 +    void finish_vertex(const Vertex& u, Graph&) { *m_iter++ = u; }
    1.47 +    
    1.48 +    OutputIterator m_iter;
    1.49 +  };
    1.50 +
    1.51 +
    1.52 +  // Topological Sort
    1.53 +  //
    1.54 +  // The topological sort algorithm creates a linear ordering
    1.55 +  // of the vertices such that if edge (u,v) appears in the graph,
    1.56 +  // then u comes before v in the ordering. The graph must
    1.57 +  // be a directed acyclic graph (DAG). The implementation
    1.58 +  // consists mainly of a call to depth-first search.
    1.59 +  //
    1.60 +
    1.61 +  template <typename VertexListGraph, typename OutputIterator,
    1.62 +    typename P, typename T, typename R>
    1.63 +  void topological_sort(VertexListGraph& g, OutputIterator result,
    1.64 +                        const bgl_named_params<P, T, R>& params)
    1.65 +  {
    1.66 +    typedef topo_sort_visitor<OutputIterator> TopoVisitor;
    1.67 +    depth_first_search(g, params.visitor(TopoVisitor(result)));
    1.68 +  }
    1.69 +
    1.70 +  template <typename VertexListGraph, typename OutputIterator>
    1.71 +  void topological_sort(VertexListGraph& g, OutputIterator result)
    1.72 +  {
    1.73 +    topological_sort(g, result, 
    1.74 +                     bgl_named_params<int, buffer_param_t>(0)); // bogus
    1.75 +  }
    1.76 +
    1.77 +} // namespace boost
    1.78 +
    1.79 +#endif /*BOOST_GRAPH_TOPOLOGICAL_SORT_H*/