Boost C++ Libraries

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libs/graph/example/subgraph.cpp

//=======================================================================
// Copyright 2001 University of Notre Dame.
// Author: 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)
//=======================================================================

/*
  Sample output:

  G0:
  0 --> 1
  1 --> 2 3
  2 --> 5
  3 -->
  4 --> 1 5
  5 --> 3
  0(0,1) 1(1,2) 2(1,3) 6(2,5) 3(4,1) 4(4,5) 5(5,3)

  G1:
  2 --> 5
  4 --> 5
  5 -->
  6(2,5) 4(4,5)

  G2:
  0 --> 1
  1 -->
  0(0,1)

 */

#include <boost/config.hpp>
#include <iostream>
#include <boost/graph/subgraph.hpp>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/graph_utility.hpp>

int main(int, char*[])
{
    using namespace boost;
    typedef subgraph< adjacency_list< vecS, vecS, directedS,
        property< vertex_color_t, int >, property< edge_index_t, int > > >
        Graph;

    const int N = 6;
    Graph G0(N);
    enum
    {
        A,
        B,
        C,
        D,
        E,
        F
    }; // for conveniently refering to vertices in G0

    Graph& G1 = G0.create_subgraph();
    Graph& G2 = G0.create_subgraph();
    enum
    {
        A1,
        B1,
        C1
    }; // for conveniently refering to vertices in G1
    enum
    {
        A2,
        B2
    }; // for conveniently refering to vertices in G2

    add_vertex(C, G1); // global vertex C becomes local A1 for G1
    add_vertex(E, G1); // global vertex E becomes local B1 for G1
    add_vertex(F, G1); // global vertex F becomes local C1 for G1

    add_vertex(A, G2); // global vertex A becomes local A1 for G2
    add_vertex(B, G2); // global vertex B becomes local B1 for G2

    add_edge(A, B, G0);
    add_edge(B, C, G0);
    add_edge(B, D, G0);
    add_edge(E, B, G0);
    add_edge(E, F, G0);
    add_edge(F, D, G0);

    add_edge(A1, C1, G1); // (A1,C1) is subgraph G1 local indices for (C,F).

    std::cout << "G0:" << std::endl;
    print_graph(G0, get(vertex_index, G0));
    print_edges2(G0, get(vertex_index, G0), get(edge_index, G0));
    std::cout << std::endl;

    Graph::children_iterator ci, ci_end;
    int num = 1;
    for (boost::tie(ci, ci_end) = G0.children(); ci != ci_end; ++ci)
    {
        std::cout << "G" << num++ << ":" << std::endl;
        print_graph(*ci, get(vertex_index, *ci));
        print_edges2(*ci, get(vertex_index, *ci), get(edge_index, *ci));
        std::cout << std::endl;
    }

    return 0;
}