1 #include<iostream> 2 using namespace std; 3 class Base{ 4     public: 5         Base(int sa) 6         { 7             a=sa; 8             cout<<"Constructing Base"<<endl; 9         }10     private://私有变量，不可在派生类中直接使用 11         int a;12 };13 class Base1:virtual public Base{14     public:15         Base1(int sa,int sb):Base (sa)16         {17             b=sb;18             cout<<"Constructing Base1"<<endl;19         }20     private:21         int b;22 }; 23 class Base2:virtual public Base{24     public:25         Base2(int sa,int sc):Base(sa)26         {27             c=sc;28             cout<<"Constructing Base2"<<endl;29         }30     private:31         int c;32 };33 class Derived:public Base1,public Base2{34     public:35         Derived(int sa,int sb,int sc,int sd)36         :Base(sa),Base1(sa,sb),Base2(sa,sc)37         //如果Base类不是虚基类，就不能使用这种方式调用基类的构造函数 38         {39             d=sd;40             cout<<"Constructing Derived"<<endl;41         }42     private:43         int d;44 };45 int main()46 {47     Derived obj(2,4,6,8);48     return 0;49 }50 51 /*52 执行结果 53 Constructing Base54 Constructing Base155 Constructing Base256 Constructing Derived57 */