第13周-程序阅读（3）

代码：

#include <iostream>
using namespace std;
class Base
{
public:
    virtual void Who() =0;
};
class FirstDerived:public Base
{
public:
    void Who() { cout<<"F"; }
};
class SecondDerived:public Base
{
public:
    void Who() { cout<<"S"; }
};
int main()
{
    FirstDerived first_obj;
    SecondDerived second_obj;
    Base &bref=first_obj;
    bref.Who();
    bref=second_obj;
    bref.Who();
    Base *bp;
    bp=&first_obj;
    bp->Who();
    bp=&second_obj;
    bp->Who();
    return 0;
}

运行结果：

FFFS
Process returned 0 (0x0)   execution time : 0.016 s
Press any key to continue.

总结：