static void printMatrix ( Fraction[][] G ){
      out.printf( "\n" );
         maxLength = 0;
         int[][] lengths = new int[rows+1][columns+1];
         for( int i = 1; i <= rows; i++){
            for ( int j = 1; j <= columns; j++ ){
               lengths[i][j] = G[i][j].length();
               if ( lengths[i][j] > maxLength )
                  maxLength = lengths[i][j];
            }
         }
         maxLength += 1;
         for ( int i = 1; i <= rows; i++ ){
            for ( int j = 1; j <= columns; j++ ){
               lengths[i][j] = maxLength - lengths[i][j];
                  while ( lengths[i][j] > 0 ){
                     out.printf( " " );
                     lengths[i][j]--;
                  }
                  G[i][j].output();
                  if ( j == columns ) System.out.print( "\n" );
            }
         }
      out.printf( "\n" );
   }