inherit.cc

#include <iostream>

class Parent {
 public:
  int x;
  virtual void print() { std::cout << "Parent" << std::endl; }
};

class Child: public Parent {
 public:
  int y;
  virtual void print() { std::cout << "Child" << std::endl; }
};

int main() {
  Parent p;
  Child c;
  Parent p2 = Child();
  Parent *p3 = new Child();

  p.print(); // Parent
  c.print(); // Child
  p2.print(); // Parent
  p3->print(); // Child
  return 0;
}