指针--实战案例

#include<iostream>
using namespace std;
class A
{
private:
    int m_a,m_b;
public:
    A()
    {
        m_a=1;
        m_b=2;
    }
    ~A() {}
    void fun()
    {
        cout<<m_a<<"   "<<m_b<<endl;
    }
};
class B
{
private:
    int m_c;
public:
    B()
    {
        m_c=3;
    }
    ~B() {}
    void fun()
    {
        cout <<m_c<<endl;
    }

};
int main ()
{
    A a;
    B *pb=(B *)(&a);
    pb->fun();

    return 0;
}

  结果：1