Difference between revisions of "CPP/Functor"

#include <iostream>
 
struct Function
{
  virtual double operator() (const double x, const double& y) const = 0;
};
 
struct Add : public Function
{
  double operator() (const double x, const double& y) const
  {
    return x+y;
  }
};
 
struct Multiply : public Function
{
  double operator() (const double x, const double& y) const
  {
    return x*y;
  }
};
 
int main(int argc, char *argv[])
{
  Function* a;
  a = new Add;
  std::cout << (*a)(2.,3.) << std::endl;
  delete a;
 
  a = new Multiply;
  std::cout << (*a)(2.,3.) << std::endl;
 
  return 0;
}