C++ Functional Library - negate

Description

It is a negative function object class and the unary function object class whose call returns the result of negating its argument (as returned by the unary operator -).

Declaration

Following is the declaration for std::negate.

template <class T> struct negate;

C++11

template <class T> struct negate;

Parameters

T − It is a type of the arguments and return type of the functional call.

Return Value

none

Exceptions

noexcep − It doesn't throw any exceptions.

Example

In below example explains about std::negate.

#include <iostream>
#include <functional>
#include <algorithm>

int main () {
   int numbers[]={100,-200,300,-40,500,-300,200};
   std::transform (numbers, numbers+5, numbers, std::negate<int>());
   for (int i=0; i<4; i++)
      std::cout << numbers[i] << ' ';
   std::cout << '\n';
   return 0;
}

Let us compile and run the above program, this will produce the following result −

-100 200 -300 40