父类的构造函数中最好不要调用虚函数

class Base{
public:
	int a;
	Base(){print();};
	virtual ~Base(){ g_iCount += 1;}
public:
	int getA(){}
	void setA(int i){}
	virtual void print(){cout<<"1"<<endl;}

};

class Derive:public Base
{
public:
	Derive(){print();}
	~Derive(){g_iCount += 2;}
public:
	void print(){cout<<"2"<<endl;}
};

void main()
{
	Derive d ;
	Base *pb = &d;
	Derive *pd = &d;

}