Function building with templates and overloading

gistfile1.cpp

#include <iostream>

template <typename Ret, typename Arg>
class Prod {
private:
	Ret (*left)(Arg);
	Ret (*right)(Arg);
public:
	Prod(Ret (*l)(Arg), Ret (*r)(Arg)) {
		this->left = l;
		this->right = r;
	}

	Ret operator()(Arg a) {
		return this->left(a)*this->right(a);
	}
};

double div3(double a) {
	return a/3.0;
}

double div2(double a) {
	return a/2.0;
}

int main(int argc, char *argv[]) {
	Prod<double, double> p = Prod<double, double>(div3, div2);
	std::cout << p(9) << std::endl;
	return 0;
}