Overloaded virtual example

overloaded-virtual.cpp

#include <cstdio>

class Base
{
public:
  virtual void foo()
  {
    fprintf(stderr, "Foo no argument\n");
  }
};

class Foo : public Base
{
public:
  virtual void foo(int bar)
  {
    fprintf(stderr, "Foo argument %d\n", bar);
  }
};

int main()
{
  Foo *x = new Foo();
  Base *y = static_cast<Base *>(x);
  x->foo(4);
  y->foo();
  delete x;
  return 0;
}