// multiple inheritance

// In C++ it is possible that a class inherits members from more than one class.
// This is done by simply separating the different base classes with commas in the
// derived class declaration. For example, if we had a specific class to print
// on screen (Output) and we wanted our classes Rectangle and Triangle to also
// inherit its members in addition to those of Polygon we could write: 

#include <iostream>
using namespace std;

class Polygon {
  protected:
    int width, height;
  public:
    void set_values (int a, int b)
      { width=a; height=b;}
  };

class Output {
  public:
    void output (int i);
  };

void Output::output (int i) {
  cout << "The output is " << i << endl;
  }

class Rectangle: public Polygon, public Output {
  public:
    int area ()
      { return (width * height); }
  };

class Triangle: public Polygon, public Output {
  public:
    int area ()
      { return (width * height / 2); }
  };
  
int main () {
  Rectangle rect;
  Triangle trgl;
  rect.set_values (4,5);
  trgl.set_values (4,5);
  rect.output (rect.area());
  trgl.output (trgl.area());
  getchar();
  return 0;
}