#include <iostream.h>


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


   Matrix3x3 operator*(Matrix3x3 &m2)
   {
      Matrix3x3 out;
      int i, j, k;
   
      for (i = 0; i < 3; i = i + 1)
      {
         for (j = 0; j < 3; j = j + 1)
         {
   	 out.A[i][j] = 0.0;
   
   	 for (k = 0; k < 3; k = k + 1)
               out.A[i][j] = out.A[i][j] + A[i][k]*m2.A[k][j];
         }
      }
   
      return(out);
   }
};



void operator<<( ostream & output, Matrix3x3 &x )          
{
   int i, j;

   for (i = 0; i < 3; i = i + 1)
   {
      for (j = 0; j < 3; j = j + 1)
         output << "  " << x.A[i][j];
      output << endl;
   }
}


int main(int argc, char *argv[])
{
   Matrix3x3 A, B, C;

   A.A[0][0] = 1.0; A.A[0][1] = 0.0; A.A[0][2] = 0.0;
   A.A[1][0] = 1.0; A.A[1][1] = 1.0; A.A[1][2] = 1.0;
   A.A[2][0] = 1.0; A.A[2][1] = 0.0; A.A[2][2] = 0.0;

   cout << "\nInitial matrix A:" << endl;
   cout << A;
   cout << endl;

   B.A[0][0] = 1.0; B.A[0][1] = 2.0; B.A[0][2] = 3.0;
   B.A[1][0] = 4.0; B.A[1][1] = 5.0; B.A[1][2] = 6.0;
   B.A[2][0] = 7.0; B.A[2][1] = 8.0; B.A[2][2] = 9.0;
   
   cout << "\nInitial matrix B:" << endl << endl;
   cout << A;
   cout << endl;

   C = A * B;
   cout << endl << "\nAfter C = A * B, matrix C:" << endl << endl;
   cout << C;
   cout << endl;

   C = B * A;
   cout << endl << "\nAfter C = B * A, matrix C:" << endl << endl;
   cout << C;
   cout << endl;
}