程序代码：

#include <iostream.h>
//using namespace std;
class sdf
{
public:
   
    int a;
    sdf(){
   
    a=3;
        cout<<"a="<<this->a<<endl;
            
    };

};
class asdf:public sdf
{
public:
    int a;
    asdf(){
a=5;
        cout<<"a="<<this->a<<endl;};
};

    asdf t;
   
int main()
{


    return 0;
}