构造函数与析构函数

#include <iostream>
using namespace std;

class A{

public:
    A()
    {
        cout<<"construct A"<<endl;
    }

    virtual void disp()
    {
        cout<<"AAAA"<<endl;
    }

    ~A()
    {
        cout<<"destory A"<<endl;
    }

};

class B:public A {

public:

    B()
    {
        cout<<"construct B"<<endl;
    }

    virtual void disp(int a)
    {
        cout<<"BBBB"<<endl;
    }

    ~B()
    {
        cout<<"destory B"<<endl;
    }
};


int main()
{
    A *a=new A();
    B *b=new B();

    delete b;

    return 0;
}