#include <cassert>
#include <boost/geometry.hpp>

namespace bg = boost::geometry;

typedef bg::model::point<double, 2, bg::cs::cartesian> point_type;
typedef bg::model::ring<point_type> ring_type;
typedef bg::model::polygon<point_type> polygon_type;
typedef bg::model::multi_polygon<polygon_type> multi_polygon_type;


int main()
{
    polygon_type pol1, pol2;
    bg::read_wkt("POLYGON((75 75,75 175,275 175,275 75,75 75))", pol1);
    bg::read_wkt("POLYGON((50 50,50 150,250 150,250 50,50 50))", pol2);

    assert(bg::is_valid(pol1));
    assert(bg::is_valid(pol2));

    multi_polygon_type mpoly;
    ring_type ring;
    bg::intersection(pol1, pol2, mpoly);
    bg::intersection(pol1, pol2, ring);
    std::cout << bg::wkt(mpoly) << std::endl;
    std::cout << bg::wkt(ring) << std::endl;
    return 0;
}