填空题

请将下列类定义补充完整。 class Base{public:void fun( ){cout＜＜"Base::fun"＜＜endl;}}; class Derived:public Base { public: void fun( ){ ______//显式调用基类的fun函数 cout＜＜"Derived::fun"＜＜endl; } };