10 11周阅读程序（3）

#include <iostream>using namespace std;class A{public:    A(char *s){cout<<s<<endl;}};class B:public A{public:    B(char *s1, char *s2):A(s1){        cout<<s2<<endl;    }};class C:public A{public:    C(char *s1,char *s2):A(s1){        cout<<s2<<endl;    }};class D:public B, C{public:    D(char *s1,char *s2,char *s3,char *s4):        B(s1,s2),C(s3,s4){cout<<s4<<endl;}};int main(){    D d("class A","class B","class C","class D");    return 0;}结果：class A    class B    class C   class D  class D