C++中使用重载()来实现闭包

class MyFunctor {public:    MyFunctor(int f) : round(f) {}    int operator()   () { return round; }private:    int round;};int main() {    const int len = 100;    MyFunctor *arr[len];    for (int i = 0; i < len; i++)    {        arr[i] = new MyFunctor(i);    }    cout << (*arr[27])() << endl;    cout << (*arr[77])() << endl;    system("pause");}