#include <boost/units/systems/si/io.hpp>
#include <boost/units/systems/si/prefixes.hpp>
#include <boost/units/base_units/metric/year.hpp>


using namespace boost::units;
using namespace boost::units::si;

using std::cout;
using std::endl;


int main()
{   
    typedef metric::year_base_unit::unit_type year_type;
    quantity<year_type> t1(7.90e16 * si::seconds); 
    cout << "Using years: " << t1 << endl;
    typedef scaled_base_unit<metric::year_base_unit, scale<10, static_rational<9> > > gigayear_base_unit;
    typedef gigayear_base_unit::unit_type gyr_type;
    quantity<gyr_type> t2(7.90e16 * si::seconds); 
    cout << "Using Gigayears: " << t2 << endl;
    return 0;
}