其实还是不明白，红色部分，，，求解
#include <iostream>
#include <time.h>using namespace std;class B0
{ public: void display() { cout<<"B0::display()"<<endl; }};class B1:public B0
{ public: void display() { cout<<"B1::display()"<<endl; }};class B2:public B0
{ public: void display() { cout<<"B2::display()"<<endl; }};void fun(B0 *ptr)
{ ptr->display();}int main()
{ B0 b0; B1 b1; B2 b2; fun(&b0);fun(&b1);
fun(&b2);
return 0;
}
输出结果都是B0.....
b0=b1;
b0=b2;
结果都是一样的；
想要改变，就要用虚函数或者不要用指针
#include <iostream>
#include <time.h>using namespace std;class B0
{ public:void display(){ cout<<"B0::display()"<<endl;}};class B1:public B0
{ public:void display(){ cout<<"B1::display()"<<endl;}};class B2:public B0
{ public:void display(){ cout<<"B2::display()"<<endl;}};
int main()
{ B0 b0;B1 b1;B2 b2;b0.display();b1.display();b2.display();b2.B0::display();return 0;
}