#include <iostream>
#include <vector>

#include <boost/geometry.hpp>
#include <boost/geometry/geometries/point_xy.hpp>
#include <boost/geometry/geometries/polygon.hpp>

int main()
{
  typedef boost::geometry::model::polygon<boost::geometry::model::d2::point_xy<double> > polygon;

  polygon green, blue;

  boost::geometry::read_wkt("POLYGON((-8042 -1485, \
                                      -8042   250, \
                                      -8042   250, \
                                      15943   254, \
                                      15943 -1485, \
                                      -8042 -1485))", green);
  
  boost::geometry::read_wkt("POLYGON((-7901 -1485, \
                                      -7901   529, \
                                      -7901   529, \
                                      15802   544, \
                                      15802 -1485, \
                                      -7901 -1485))", blue);
  
  boost::geometry::correct(green);
  boost::geometry::correct(blue);

  std::vector<polygon> output1;
  boost::geometry::difference(green, blue, output1);

  unsigned int i = 0;

  for (auto const & p : output1)
  {
    std::cout << "polygon #" << i++ << ": ";

    for (auto const & n : p.outer())
    {
      std::cout << "(" << n.x() << "," << n.y() << ") ";
    }

    std::cout << std::endl;
  }

  std::cout << "----" << std::endl;

  std::vector<polygon> output2;
  boost::geometry::difference(blue, green, output2);

  unsigned int j = 0;

  for (auto const & p : output2)
  {
    std::cout << "polygon #" << j++ << ": ";

    for (auto const & n : p.outer())
    {
      std::cout << "(" << n.x() << "," << n.y() << ") ";
    }

    std::cout << std::endl;
  }

  return 0;
}