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// (C) Copyright Andrew Sutton 2007
//
// Use, modification and distribution are subject to the
// Boost Software License, Version 1.0 (See accompanying file
// LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
//[tiernan_print_cycles
#include <iostream>
#include <boost/graph/directed_graph.hpp>
#include <boost/graph/tiernan_all_cycles.hpp>
#include "helper.hpp"
using namespace std;
using namespace boost;
// The cycle_printer is a visitor that will print the path that comprises
// the cycle. Note that the back() vertex of the path is not the same as
// the front(). It is implicit in the listing of vertices that the back()
// vertex is connected to the front().
template <typename OutputStream>
struct cycle_printer
{
cycle_printer(OutputStream& stream)
: os(stream)
{ }
template <typename Path, typename Graph>
void cycle(const Path& p, const Graph& g)
{
// Get the property map containing the vertex indices
// so we can print them.
typedef typename property_map<Graph, vertex_index_t>::const_type IndexMap;
IndexMap indices = get(vertex_index, g);
// Iterate over path printing each vertex that forms the cycle.
typename Path::const_iterator i, end = p.end();
for(i = p.begin(); i != end; ++i) {
os << get(indices, *i) << " ";
}
os << endl;
}
OutputStream& os;
};
// Declare the graph type and its vertex and edge types.
typedef directed_graph<> Graph;
typedef graph_traits<Graph>::vertex_descriptor Vertex;
typedef graph_traits<Graph>::edge_descriptor Edge;
int
main(int argc, char *argv[])
{
// Create the graph and read it from standard input.
Graph g;
read_graph(g, cin);
// Instantiate the visitor for printing cycles
cycle_printer<ostream> vis(cout);
// Use the Tiernan algorithm to visit all cycles, printing them
// as they are found.
tiernan_all_cycles(g, vis);
return 0;
}
//]
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