#include <iostream>
 
struct Base
{
  virtual void test() { std::cout << "Base" << std::endl; }
};
struct Derived : Base
{
  virtual void test() { std::cout << "Derived" << std::endl; }
};
 
void f(Base *base) { base->test(); }
void g(Base &base) { base.test();  }
void h(Base base)  { base.test();  }
 
int main()
{
  Derived d;
  Derived *dp = &d;
  Base    *bp = dp;
 
  f(dp); // Derived
  f(bp); // Derived
  g(d);  // Derived
  h(d);  // Base
 
  return 0;
}

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