• num, Numerator
• den, Denominator

#include <iostream>
#include <ratio>

int main(int argc, char *argv[])
{
	std::ratio<1, 3> oneThird;//variable
	std::cout<<oneThird.num<<"/"<<oneThird.den<<std::endl;

	typedef std::ratio<2, 4> twoFourth;//variable type
	std::cout<<twoFourth::num<<"/"<<twoFourth::den<<std::endl;

	//ratio_add
	typedef std::ratio_add<decltype(oneThird), twoFourth> sum;
	std::cout<<sum::num<<"/"<<sum::den<<std::endl;

	return 0;
}
			

#include <iostream>
#include <ratio>

int main(int argc, char *argv[])
{
	//std::milli
	std::cout<<std::milli::num<<"/"<<std::milli::den<<std::endl;

	return 0;
}
		

• cplusplus.com