class template
<functional>
std::minus
template <class T> struct minus;
Subtraction function object class
Binary function object class whose call returns the result of subtracting its second argument from its first argument (as returned by the binary operator -).
Generically, function objects are instances of a class with member function operator() defined. This member function allows the object to be used with the same syntax as a function call.
It is defined with the same behavior as:
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| template <class T> struct minus : binary_function <T,T,T> { T operator() (const T& x, const T& y) const {return x-y;} };
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| template <class T> struct minus { T operator() (const T& x, const T& y) const {return x-y;} typedef T first_argument_type; typedef T second_argument_type; typedef T result_type; };
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Objects of this class can be used on standard algorithms such as transform or accumulate.
Template parameters
- T
- Type of the arguments and return type of the functional call.
The type shall support the operation (binary operator-).
Member types
| member type | definition | notes |
|---|
| first_argument_type | T | Type of the first argument in member operator() |
| second_argument_type | T | Type of the second argument in member operator() |
| result_type | T | Type returned by member operator() |
Member functions
- T operator() (const T& x, const T& y)
- Member function returning the subtraction of its arguments (
x-y).
Example
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| // minus example #include <iostream> // std::cout #include <functional> // std::minus #include <algorithm> // std::transform int main () { int numbers[]={10,20,30}; int result; result = std::accumulate (numbers, numbers+3, 100, std::minus<int>()); std::cout << "The result of 100-10-20-30 is " << result << ".\n"; return 0; }
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Output:
The result of 100-10-20-30 is 40. |
See also
- plus
- Addition function object class (class template)
- multiplies
- Multiplication function object class (class template)
- divides
- Division function object class (class template)
- modulus
- Modulus function object class (class template)
- negate
- Negative function object class (class template)
- equal_to
- Function object class for equality comparison (class template)