// Copyright (c) Jeremy Siek 2001, Marc Wintermantel 2002

 //

 // 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_BANDWIDTH_HPP

 #define BOOST_GRAPH_BANDWIDTH_HPP

 #include <algorithm> // for std::min and std::max

 #include <boost/config.hpp>

 #include <boost/graph/graph_traits.hpp>

 #include <boost/detail/numeric_traits.hpp>

 namespace boost {

   template <typename Graph, typename VertexIndexMap>

   typename graph_traits<Graph>::vertices_size_type

   ith_bandwidth(typename graph_traits<Graph>::vertex_descriptor i,

                 const Graph& g,

                 VertexIndexMap index)

   {

     BOOST_USING_STD_MAX();

     typedef typename graph_traits<Graph>::vertices_size_type size_type;

     size_type b = 0;

     typename graph_traits<Graph>::out_edge_iterator e, end;

     for (tie(e, end) = out_edges(i, g); e != end; ++e) {

       int f_i = get(index, i);

       int f_j = get(index, target(*e, g));

       using namespace std; // to call abs() unqualified

       if(f_i > f_j)

           b = max BOOST_PREVENT_MACRO_SUBSTITUTION (b, size_type(f_i - f_j));

     }

     return b;

   }

   template <typename Graph>

   typename graph_traits<Graph>::vertices_size_type

   ith_bandwidth(typename graph_traits<Graph>::vertex_descriptor i,

                 const Graph& g)

   {

     return ith_bandwidth(i, g, get(vertex_index, g));

   }

   template <typename Graph, typename VertexIndexMap>

   typename graph_traits<Graph>::vertices_size_type

   bandwidth(const Graph& g, VertexIndexMap index)

   {

     BOOST_USING_STD_MAX();

     typename graph_traits<Graph>::vertices_size_type b = 0;

     typename graph_traits<Graph>::vertex_iterator i, end;

     for (tie(i, end) = vertices(g); i != end; ++i)

         b = max BOOST_PREVENT_MACRO_SUBSTITUTION (b, ith_bandwidth(*i, g, index));

     return b;

   }

   template <typename Graph>

   typename graph_traits<Graph>::vertices_size_type

   bandwidth(const Graph& g)

   {

     return bandwidth(g, get(vertex_index, g));

   }

   template <typename Graph, typename VertexIndexMap>

   typename graph_traits<Graph>::vertices_size_type

   edgesum(const Graph& g, VertexIndexMap index_map)

   {

     typedef typename graph_traits<Graph>::vertices_size_type size_type;

     typedef typename detail::numeric_traits<size_type>::difference_type diff_t;

     size_type sum = 0;

     typename graph_traits<Graph>::edge_iterator i, end;

     for (tie(i, end) = edges(g); i != end; ++i) {

       diff_t f_u = get(index_map, source(*i, g));

       diff_t f_v = get(index_map, target(*i, g));

       using namespace std; // to call abs() unqualified

       sum += abs(f_u - f_v);

     }

     return sum;

   }

 } // namespace boost

 #endif // BOOST_GRAPH_BANDWIDTH_HPP