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