如何在销毁对象时解决逻辑错误？

Question

这里我遇到了对象的析构函数中的问题。在下面给出的程序中，我试图动态地使用基类指针创建对象，当我尝试删除时指针比指针只删除 A 的对象。 那么如何在程序结束时删除所有对象？

class A{
         public:
            A(){
            cout<<"Object A is created "<<endl;
            }
            ~A(){
             cout<<"Object A is destroyed"<<endl;
             }
       };
class B{
        public:
          B(){
          cout<<"object B is Created \n";
          }
          ~B(){
           cout<<"Object B is Destroyed"<<endl;
           }
       };
class C{
        public:
          C(){
          cout<<"constructor of C class"<<endl;
          }
          ~C(){
           cout<<"destructor of C "<<endl;
           }
       };
class D:public C, public B, public A{
     public:
       D(){
       cout<<"Object D is created "<<endl;
       }
       ~D(){
        cout<<"Object D is destroyed "<<endl;
        }
  };
int main()
{
   A *a;
   a = new D();
   delete a;
   return 0;
}

Answer 1

将基类的析构函数声明为虚拟。

请阅读this了解原因。