class A{
public: A(){cout<<"A+"<<endl;}
public: ~A(){cout<<"A-"<<endl;}
};
class B :public A{
public: B(){cout<<"B+"<<endl;}
public: ~B(){cout<<"B-"<<endl;}
};
A a;
int main(){
cout<<"start main"<<endl;
B b;
cout<<"end main"<<endl;
return 0;
}
输出:A+ start main A+ B+ end main B−A−A−{\orange{输出:A+\ start\ main\ A+\ B+\ end\ main\ B- A- A-}}输出:A+ start main A+ B+ end main B−A−A−