#include <iostream>
using namespace std;
 
class Base{
public:
   Base(){};
   virtual ~Base() {};
   virtual void foomethod()=0; //Marked as pure virtual
};
 
class A : public Base{
public:	
   A(){};  //Ctor
   virtual ~A(){}; //Dtor
   void foomethod(){ cout << "Hello from A"; }
};
class B : public Base{
public:
   B(){};  //Ctor
   virtual ~B(){}; //Dtor
   void foomethod(){ /* DO SOMETHING */ }
};
 
int main() {
 
	// Base obj; // Can't do that
	Base *obj = new A();
	obj->foomethod(); // A's one
	delete obj;
 
    return 0;
}

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