#include <math.h>
#include <boost/multiprecision/cpp_bin_float.hpp>

typedef boost::multiprecision::number
  <boost::multiprecision::backends::cpp_bin_float<256, boost::multiprecision::backends::digit_base_2> >
  ext_float_t;

int main(int, char**) {
  ext_float_t x = 1e7+0.5;
  ext_float_t x1 = x + ldexp(255, -38); // + 2^-30 - eps
  ext_float_t x2 = x + ldexp(257, -38); // + 2^-30 + eps
  float f1 = x1.convert_to<float>();
  float f2 = x2.convert_to<float>();
  std::cout <<  std::setprecision(27);
  std::cout << "x1=" << x1 << " => " << f1 << "\n";
  std::cout << "x2=" << x2 << " => " << f2 << "\n";
  if (f1==f2)
    std::cout << "good\n";
  else
    std::cout << "bad\n";

  return 0;
}