std::ratio_add

Since C++11

Header: <ratio>

The alias template std::ratio_add denotes the result of adding two exact rational fractions represented by the std::ratio specializations R1 and R2.

# Declarations

template< class R1, class R2 >
using ratio_add = /* see below */;

(since C++11)

# Notes

If U or V is not representable in std::intmax_t, the program is ill-formed. If Num or Denom is not representable in std::intmax_t, the program is ill-formed unless the implementation yields correct values for U and V.

The above definition requires that the result of std::ratio_add<R1, R2> be already reduced to lowest terms; for example, std::ratio_add<std::ratio<1, 3>, std::ratio<1, 6» is the same type as std::ratio<1, 2>.

# Example

#include <iostream>
#include <ratio>
 
int main()
{
    using two_third = std::ratio<2, 3>;
    using one_sixth = std::ratio<1, 6>;
    using sum = std::ratio_add<two_third, one_sixth>;
 
    std::cout << "2/3 + 1/6 = " << sum::num << '/' << sum::den << '\n';
}

# See also