/* @ pure */ public boolean isSideField(Coordinate coord) {
		boolean result = false;
		int x = coord.getX();
		int y = coord.getY();
		if (isField(coord.getIndex()) && (x == 0 || y == 0 || x == DIM - 1 || y == DIM - 1)) {
			result = true;
		}
		return result;
	}