将函数调用运算符“()”进行重载：

#include<iostream>
using namespace std;
class Add
{
	public:
		double operator ()(double a,double b);
};
double Add::operator() (double a,double b)
{
	return a+b;
}
int main()
{
	Add f;
	cout<<f(2.5,3.2)<<endl;
	return 0;
}

重载函数调用运算符