class template
<functional>

std::modulus

template <class T> struct modulus;
Modulus function object class
Binary function object class whose call returns the result of the modulus operation between its two arguments (as returned by 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 modulus : 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 modulus {
  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;
};


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 (operator%).

Member types

member typedefinitionnotes
first_argument_typeTType of the first argument in member operator()
second_argument_typeTType of the second argument in member operator()
result_typeTType returned by member operator()

Member functions

T operator() (const T& x, const T& y)
Member function returning the modulus operation between its arguments (x%y).

Example

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// modulus example
#include <iostream>     // std::cout
#include <functional>   // std::modulus, std::bind2nd
#include <algorithm>    // std::transform

int main () {
  int numbers[]={1,2,3,4,5};
  int remainders[5];
  std::transform (numbers, numbers+5, remainders, std::bind2nd(std::modulus<int>(),2));
  for (int i=0; i<5; i++)
    std::cout << numbers[i] << " is " << (remainders[i]==0?"even":"odd") << '\n';
  return 0;
}


Output:

1 is odd
2 is even
3 is odd
4 is even
5 is odd

See also

plus
Addition function object class (class template )
minus
Subtraction function object class (class template )
multiplies
Multiplication function object class (class template )
divides
Division function object class (class template )
negate
Negative function object class (class template )
equal_to
Function object class for equality comparison (class template )

C++