Создать копию объекта производного класса зная указатель на базовый

#include <iostream>
 
using namespace std;
 
class Base
{
public:
  Base()
  {
     cout<<"Base constructor default"<<endl;
  };
  
  Base(const Base& obj)
  {
     cout<<"Base constructor copy"<<endl;
  };
  virtual ~Base() {;}
};
 
class Derived1:public Base
{
  public:
  Derived1()
  {
    cout<<"Derived1 constructor default"<<endl;
  }
 
  Derived1(const Derived1& obj)
  {
    cout<<"Derived1 constructor copy"<<endl;;
  }
};
 
class Derived2:public Base
{
  public:
  Derived2()
  {
    cout<<"Derived2 constructor default"<<endl;
  }
 
  Derived2(const Derived2& obj)
  {
    cout<<"Derived2 constructor copy"<<endl;;
  }
};
 
void clone(Base* pBase)
{
  cout<<"clone object"<<endl;
  if (Derived1 *p=dynamic_cast<Derived1*>(pBase)) new Derived1(*p) ;
  if (Derived2 *p=dynamic_cast<Derived2*>(pBase)) new Derived2(*p) ;
}
 
void main()
{
  Derived1 d1;
  Derived2 d2;
  Base* pBase =&d1;
  clone(pBase);
  pBase =&d2;
  clone(pBase);
}

template <class T>
void clone(T pBase)
{
  cout<<"clone object"<<endl;
  if (Derived1 *p=dynamic_cast<Derived1*>(pBase)) new Derived1(*p) ;
  if (Derived2 *p=dynamic_cast<Derived2*>(pBase)) new Derived2(*p) ;
  ...
}

class Base
{
public:
    virtual Base* clone() { return this; }
    virtual ~Base() {}
};
 
class Der1: public Base
{
    char c;
public:
    Der1(): c('m') {}
};
class Der2: public Base
{
    int n;
public:
    Der2(): n(682) {}
};
 
std::vector<Base*> list;
void func(Base *b) {
    Base *ptr = new Base(*b);
    ptr = b->clone();
    list.push_back(ptr);
}
 
int main()
{
    Der1 d;
    Der2 dd;
    func(&d);
    func(&dd);
 
    system("PAUSE");
    return 0;
}

class Base
{
public:
    virtual Base* clone() { return 0; }
    virtual ~Base() {}
};
 
class Der1: public Base
{
    char c;
 
public:
    Der1(): c('m') {}
    
    char& getc() { return c; }
 
    virtual Base* clone() {
        Der1 *p = new Der1;
        p->c = c;
        return p;
    }
};
class Der2: public Base
{
    int n;
public:
    Der2(): n(682) {}
 
    virtual Base* clone() {
        Der2 *p = new Der2;
        p->n = n;
        return p;
    }
};
 
std::vector<Base*> vvv;
void func(Base *b) {
    Base *ptr = b->clone();
    vvv.push_back(ptr);
}
 
int main()
{
    Node n1, n2, n3;
    Manager::ModifyNode(&n2);
    Manager::undoLast();
 
    Der1 d; //d.c = 'm';
    Der2 dd; //dd.n = 546;
    func(&d);
    func(&dd);
    d.getc() = 'a';
 
    system("PAUSE");
    return 0;
}