C++11: Time: Durations

C++11 has new duration types that can be used with the new time functions.

#include <chrono>
#include <iostream>

int main()
{
  std::chrono::nanoseconds  ns(9'000'000);
  std::chrono::microseconds us(60'000);
  std::chrono::milliseconds ms(300);
  std::chrono::seconds       s(1);

  std::chrono::high_resolution_clock::duration hrc_duration = s + ms + us + ns;

  double hrc_seconds = double(hrc_duration.count())                    *
                       std::chrono::high_resolution_clock::period::num /
                       std::chrono::high_resolution_clock::period::den;  

  std::cout << hrc_seconds << std::endl;

  return 0;
}
// Output: 1.369

Reference: http://en.cppreference.com/w/cpp/chrono/duration