BGL_surface_mesh/connected_components.cpp

#include <CGAL/Simple_cartesian.h>
#include <CGAL/Surface_mesh.h>
 
#include <iostream>
#include <fstream>
 
#include <boost/graph/connected_components.hpp>
 
typedef CGAL::Simple_cartesian<double>                       Kernel;
typedef Kernel::Point_3                                      Point;
typedef CGAL::Surface_mesh<Point>                            Mesh;
 
typedef boost::graph_traits<Mesh>::vertex_descriptor vertex_descriptor;
 
int main(int argc, char* argv[])
{
  const std::string filename = (argc > 1) ? argv[1] : CGAL::data_file_path("meshes/prim.off");
 
  Mesh sm;
  if(!CGAL::IO::read_polygon_mesh(filename, sm))
  {
    std::cerr << "Invalid input." << std::endl;
    return 1;
  }
 
  Mesh::Property_map<vertex_descriptor,int> ccmap;
  ccmap = sm.add_property_map<vertex_descriptor,int>("v:CC").first;
 
  int num = connected_components(sm, ccmap);
  std::cout  << num << " connected components" << std::endl;
  for(vertex_descriptor v : vertices(sm)){
    std::cout  << v << " is in component " << ccmap[v] << std::endl;
  }
 
  return 0;
}