Boost C++ Libraries

libs/graph/example/ordered_out_edges.cpp

//=======================================================================
// 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)
//=======================================================================

/*
   IMPORTANT:
   ~~~~~~~~~~

   This example appears to be broken and crashes at runtime, see
   https://github.com/boostorg/graph/issues/149

*/

#include <boost/config.hpp>
#include <iostream>
#include <functional>
#include <string>

#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/properties.hpp>

/*
  Sample output:

  0  --chandler--> 1   --joe--> 1
  1  --chandler--> 0   --joe--> 0   --curly--> 2   --dick--> 3   --dick--> 3
  2  --curly--> 1   --tom--> 4
  3  --dick--> 1   --dick--> 1   --harry--> 4
  4  --tom--> 2   --harry--> 3

  name(0,1) = chandler

  name(0,1) = chandler
  name(0,1) = joe

 */

template < class StoredEdge > struct order_by_name
{
    typedef StoredEdge first_argument_type;
    typedef StoredEdge second_argument_type;
    typedef bool result_type;
    bool operator()(const StoredEdge& e1, const StoredEdge& e2) const
    {
        // Order by target vertex, then by name.
        // std::pair's operator< does a nice job of implementing
        // lexicographical compare on tuples.
        return std::make_pair(e1.get_target(), boost::get(boost::edge_name, e1))
            < std::make_pair(e2.get_target(), boost::get(boost::edge_name, e2));
    }
};

#if !defined BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
struct ordered_set_by_nameS
{
};
namespace boost
{
template < class ValueType >
struct container_gen< ordered_set_by_nameS, ValueType >
{
    typedef std::multiset< ValueType, order_by_name< ValueType > > type;
};
}
#else
struct ordered_set_by_nameS
{
    template < class T > struct bind_
    {
        typedef std::multiset< T, order_by_name< T > > type;
    };
};
namespace boost
{
template <> struct container_selector< ordered_set_by_nameS >
{
    typedef ordered_set_by_nameS type;
};
}
#endif

namespace boost
{
template <> struct parallel_edge_traits< ordered_set_by_nameS >
{
    typedef allow_parallel_edge_tag type;
};
}

int main()
{
#ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
    std::cout << "This program requires partial specialization" << std::endl;
#else
    using namespace boost;
    typedef property< edge_name_t, std::string > EdgeProperty;
    typedef adjacency_list< ordered_set_by_nameS, vecS, undirectedS,
        no_property, EdgeProperty >
        graph_type;
    graph_type g;

    add_edge(0, 1, EdgeProperty("joe"), g);
    add_edge(1, 2, EdgeProperty("curly"), g);
    add_edge(1, 3, EdgeProperty("dick"), g);
    add_edge(1, 3, EdgeProperty("dick"), g);
    add_edge(2, 4, EdgeProperty("tom"), g);
    add_edge(3, 4, EdgeProperty("harry"), g);
    add_edge(0, 1, EdgeProperty("chandler"), g);

    property_map< graph_type, vertex_index_t >::type id = get(vertex_index, g);
    property_map< graph_type, edge_name_t >::type name = get(edge_name, g);

    graph_traits< graph_type >::vertex_iterator i, end;
    graph_traits< graph_type >::out_edge_iterator ei, edge_end;
    for (boost::tie(i, end) = vertices(g); i != end; ++i)
    {
        std::cout << id[*i] << " ";
        for (boost::tie(ei, edge_end) = out_edges(*i, g); ei != edge_end; ++ei)
            std::cout << " --" << name[*ei] << "--> " << id[target(*ei, g)]
                      << "  ";
        std::cout << std::endl;
    }
    std::cout << std::endl;

    bool found;
    typedef graph_traits< graph_type > Traits;
    Traits::edge_descriptor e;
    Traits::out_edge_iterator e_first, e_last;

    boost::tie(e, found) = edge(0, 1, g);
    if (found)
        std::cout << "name(0,1) = " << name[e] << std::endl;
    else
        std::cout << "not found" << std::endl;
    std::cout << std::endl;

    boost::tie(e_first, e_last) = edge_range(0, 1, g);
    while (e_first != e_last)
        std::cout << "name(0,1) = " << name[*e_first++] << std::endl;
#endif
    return 0;
}