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131 lines
4.2 KiB
C++
131 lines
4.2 KiB
C++
//=======================================================================
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// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
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// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
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//
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// This file is part of the Boost Graph Library
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//
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// You should have received a copy of the License Agreement for the
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// Boost Graph Library along with the software; see the file LICENSE.
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// If not, contact Office of Research, University of Notre Dame, Notre
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// Dame, IN 46556.
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//
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// Permission to modify the code and to distribute modified code is
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// granted, provided the text of this NOTICE is retained, a notice that
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// the code was modified is included with the above COPYRIGHT NOTICE and
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// with the COPYRIGHT NOTICE in the LICENSE file, and that the LICENSE
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// file is distributed with the modified code.
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//
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// LICENSOR MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED.
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// By way of example, but not limitation, Licensor MAKES NO
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// REPRESENTATIONS OR WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY
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// PARTICULAR PURPOSE OR THAT THE USE OF THE LICENSED SOFTWARE COMPONENTS
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// OR DOCUMENTATION WILL NOT INFRINGE ANY PATENTS, COPYRIGHTS, TRADEMARKS
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// OR OTHER RIGHTS.
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//=======================================================================
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#include <iostream>
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#include <vector>
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#include <algorithm>
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#include <utility>
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#include <boost/graph/adjacency_list.hpp>
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#include <boost/graph/connected_components.hpp>
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/*
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This example demonstrates the usage of the connected_components
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algorithm on a directed and undirected graph. The example graphs
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come from "Introduction to Algorithms", Cormen, Leiserson, and
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Rivest p. 87 (though we number the vertices from zero instead of
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one).
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Sample output:
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An undirected graph:
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Total number of components: 3
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Vertex 0 is in component 0
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Vertex 1 is in component 0
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Vertex 2 is in component 1
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Vertex 3 is in component 2
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Vertex 4 is in component 0
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Vertex 5 is in component 1
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A directed graph:
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Total number of components: 3
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Vertex 0 is in component 2
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Vertex 1 is in component 2
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Vertex 2 is in component 1
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Vertex 3 is in component 2
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Vertex 4 is in component 2
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Vertex 5 is in component 0
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*/
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using namespace std;
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int main(int , char* [])
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{
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// First example: the connected components of an undirected graph
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using namespace boost;
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{
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typedef property<vertex_discover_time_t, int,
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property< vertex_finish_time_t, int,
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property< vertex_color_t, default_color_type > > > VertexProperty;
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typedef adjacency_list <vecS, vecS, undirectedS, VertexProperty> Graph;
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typedef graph_traits<Graph>::vertex_descriptor Vertex;
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Graph G;
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add_edge(0, 1, G);
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add_edge(1, 4, G);
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add_edge(4, 0, G);
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add_edge(2, 5, G);
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std::vector<int> c(num_vertices(G));
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int num = connected_components(G, &c[0], get(vertex_color, G),
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dfs_visitor<>());
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cout << "An undirected graph:" << endl;
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cout << endl;
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std::vector<int>::iterator i;
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cout << "Total number of components: " << num << endl;
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for (i = c.begin(); i != c.end(); ++i)
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cout << "Vertex " << i - c.begin() <<" is in component " << *i << endl;
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cout << endl;
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}
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// Second example: the strongly connected components of a directed
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// graph
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{
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typedef property<vertex_discover_time_t, int,
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property< vertex_finish_time_t, int,
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property< vertex_color_t, default_color_type > > > VertexProperty;
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typedef adjacency_list< vecS, vecS, directedS, VertexProperty > Graph;
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Graph G;
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add_edge(0, 1, G);
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add_edge(1, 1, G);
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add_edge(1, 3, G);
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add_edge(1, 4, G);
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add_edge(4, 3, G);
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add_edge(3, 4, G);
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add_edge(3, 0, G);
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add_edge(5, 2, G);
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typedef graph_traits<Graph>::vertex_descriptor Vertex;
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std::vector<int> c(num_vertices(G));
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int num = connected_components(G, &c[0], get(vertex_color, G),
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dfs_visitor<>());
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cout << "A directed graph:" << endl;
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cout << endl;
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cout << "Total number of components: " << num << endl;
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std::vector<int>::iterator i;
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for (i = c.begin(); i != c.end(); ++i)
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cout << "Vertex " << i - c.begin() <<" is in component " << *i << endl;
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}
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return 0;
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}
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