Prototype design pattern example (c++)

I am learning Prototype design pattern and get confused from an example represented on this article by sourcemaking.

class Stooge
{
public:
   virtual void slap_stick() = 0;
   virtual Stooge* clone() = 0;
};

class Larry : public Stooge
{
public:
   void slap_stick()
   {
      cout << "Larry: poke eyes\n";
   }
   Stooge*   clone() { return new Larry; }   
};
class Moe : public Stooge
{
public:
   void slap_stick()
   {
      cout << "Moe: slap head\n";
   }
   Stooge*   clone() { return new Moe; }   
};
class Curly : public Stooge
{
public:
   void slap_stick()
   {
      cout << "Curly: suffer abuse\n";
   }
   Stooge*   clone() { return new Curly; }
};

class Factory
{
public:
   static Stooge* make_stooge( int choice );
private:
   static Stooge* s_prototypes[4];
};

Stooge* Factory::s_prototypes[] = {0, new Larry, new Moe, new Curly};

Stooge* Factory::make_stooge( int choice )
{
   return s_prototypes[choice]->clone();
}

int main()
{
   vector roles;
   int    choice;

   while (true)
   {
      cout << "Larry(1) Moe(2) Curly(3) Go(0): ";
      cin >> choice;
      if (choice == 0)
         break;
      roles.push_back(Factory::make_stooge( choice ) );
   }

   for (int i=0; i < roles.size(); ++i)
      roles[i]->slap_stick();
   for (int i=0; i < roles.size(); ++i)
      delete roles[i];
}

According to description Prototype Design Pattern

• Specify the kinds of objects to create using a prototypical instance, and create new objects by copying this prototype.

According to this. The prototype design pattern is a design pattern that is used to instantiate a class by copying, or cloning, the properties of an existing object.

As far as I know, the normal way of copying a class is to use copy constructors, overload operator=, or implement clone function to instantiate a new object by copying all of the properties of an existing object.

On the example above, I do not see how it achieves creating new objects by copying the prototype, as nor copy constructors, neither overload operator=, or appropriate clone function defined.

So can I assume that this is not an implementation of prototype design pattern? Or maybe I am wrong on my assumptions and do not understand this example?