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Shared Pointer : Alternative to Virtual Destruct

When a base class points to a derived class object and when delete gets called on pointer then only base class destructor gets called.

 Solution 1: 
TO overcome this issue, make base class destructor as virtual. With this change, both the derived class and base class destructor gets called.
Solutions 2 : Using Shared_ptr

 class Dog {
public:
   ~Dog() {  cout << "Dog is destroyed"; }
};

 class Yellowdog : public Dog {
public:
   ~Yellowdog() {cout << "Yellow dog destroyed." <
};
class DogFactory {
public:
   //static Dog* createYellowDog() { return (new Yellowdog()); }
   static shared_ptr createYellowDog() { 
      return shared_ptr(new Yellowdog()); 
   }
   
//Connot  useful through Unique_ptr in this case
//static unique_ptr createYellowDog() {
   //   return unique_ptr(new Yellowdog());
   //}

 };

 int main() {

    //Dog* pd = DogFactory::createYellowDog();
   shared_ptr pd = DogFactory::createYellowDog();
   //unique_ptr pd = DogFactory::createYellowDog();
   
   //delete pd;
   
return 0;
}
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