#include <iostream.h>

class Vector3;

class Matrix3x3
{
private:
   double A[3][3];

public:
   Matrix3x3();
   Matrix3x3(double a, double b, double c, 
           double d, double e, double f, 
           double g, double h, double i );
   Vector3 operator*(Vector3 & v);

   friend ostream & operator<<(ostream &, Matrix3x3 &);

   friend class Vector3;
};