Позвольте мне задать свой вопрос по этой тестовой программе:

#include 
#include 

using std::chrono::nanoseconds;
using std::chrono::duration_cast;

int main(int argc, char* argv[])
{
    std::cout < "resolution (nano) = " < (double) std::chrono::high_resolution_clock::period::num
        / std::chrono::high_resolution_clock::period::den * 1000 * 1000 * 1000 < std::endl;

    auto t1 = std::chrono::high_resolution_clock::now();
    std::cout < "how much nanoseconds std::cout takes?" < std::endl;
    auto t2 = std::chrono::high_resolution_clock::now();


    auto diff = t2-t1;
    nanoseconds ns = duration_cast