重载、虚函数（覆盖、多态）、隐藏 -- 代码示例

复习重载、虚函数（覆盖、多态）、隐藏，方便理解：

class Base{public:virtual int A();int foo(void);int foo(int);// 重载函数foo()int a;protected:int B();int b;private:virtual int C();int C(Base* pBase);int c;public:Base* pbase;};int Base::A(){a = 1;return a;}int Base::B(){b = 2;return b;}int Base::C(){c = 3;return c;}int Base::C(Base* pBase){// 可以访问pBase的所有属性成员函数// 包括protected和private属性成员函数return pBase->C(); // OK}class Derived: public Base{public:virtual int A();// 虚函数、多态、覆盖int foo(double);// 隐藏基类函数foo()int a;protected:int B();// 隐藏基类函数int b;int foo(long);// 隐藏基类函数foo()、该类内部的foo(double)构成重载关系private:virtual int C();// 多态、覆盖、虚函数int C(Base* pBase);int c;public:Derived* pdrived;};int Derived::A(){a = 4;return a;}int Derived::B(){b = 5;return b;}int Derived::C(){c = 6;return c;}int Derived::C(Base* pBase){// 只能访问pBase的public属性成员函数return pBase->A();}