class Func {
public:
    template <typename T>
    void operator()(T& x, const T& y) {
        x = y;
    }
};

class Point {
public:
    Func f;
};

class Assain {
private:
    Point *sub;
public:
    Assain() : sub(new Point) {}
    ~Assain() { delete sub; }
    Point*operator->() {
        return sub;
    }
};