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-rw-r--r-- | src/boost/libs/graph/example/incremental-components-eg.cpp | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/src/boost/libs/graph/example/incremental-components-eg.cpp b/src/boost/libs/graph/example/incremental-components-eg.cpp new file mode 100644 index 00000000..7faf4418 --- /dev/null +++ b/src/boost/libs/graph/example/incremental-components-eg.cpp @@ -0,0 +1,84 @@ +//======================================================================= +// Copyright 2001 Jeremy G. Siek, Andrew Lumsdaine, Lie-Quan Lee, +// Copyright 2009 Trustees of Indiana University. +// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek, Michael Hansen +// +// 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) +//======================================================================= + +#include <iostream> +#include <vector> + +#include <boost/foreach.hpp> +#include <boost/graph/adjacency_list.hpp> +#include <boost/graph/incremental_components.hpp> +#include <boost/pending/disjoint_sets.hpp> + +using namespace boost; + +int main(int argc, char* argv[]) +{ + typedef adjacency_list <vecS, vecS, undirectedS> Graph; + typedef graph_traits<Graph>::vertex_descriptor Vertex; + //typedef graph_traits<Graph>::edge_descriptor Edge; + typedef graph_traits<Graph>::vertices_size_type VertexIndex; + + // Create a graph + const int VERTEX_COUNT = 6; + Graph graph(VERTEX_COUNT); + + add_edge(0, 1, graph); + add_edge(1, 4, graph); + + // reate the disjoint-sets object, which requires rank and parent + // vertex properties. + std::vector<Vertex> rank(num_vertices(graph)); + std::vector<Vertex> parent(num_vertices(graph)); + + typedef VertexIndex* Rank; + typedef Vertex* Parent; + disjoint_sets<Rank, Parent> ds(&rank[0], &parent[0]); + + // Determine the connected components, storing the results in the + // disjoint-sets object. + initialize_incremental_components(graph, ds); + incremental_components(graph, ds); + + // Add a couple more edges and update the disjoint-sets + add_edge(4, 0, graph); + add_edge(2, 5, graph); + + ds.union_set(4, 0); + ds.union_set(2, 5); + + BOOST_FOREACH(Vertex current_vertex, vertices(graph)) { + std::cout << "representative[" << current_vertex << "] = " << + ds.find_set(current_vertex) << std::endl; + } + + std::cout << std::endl; + + // Generate component index. NOTE: We would need to pass in a vertex + // index map into the component_index constructor if our graph type + // used listS instead of vecS (identity_property_map is used by + // default). + typedef component_index<VertexIndex> Components; + Components components(parent.begin(), parent.end()); + + // Iterate through the component indices + BOOST_FOREACH(VertexIndex component_index, components) { + std::cout << "component " << component_index << " contains: "; + + // Iterate through the child vertex indices for [component_index] + BOOST_FOREACH(VertexIndex child_index, + components[component_index]) { + std::cout << child_index << " "; + } + + std::cout << std::endl; + } + + return (0); +} |