private boolean labyrinth(int i, int j, int height, int length) {
        ArrayList<Integer> possibile = new ArrayList<Integer>();
        for (int s=4;s<length-3;s=s+3) {
            possibile.add(s);
        }
        return j>3 && j<height-3 && (possibile.contains(i)) && j!=height/2 && j!=height/2-1;
    }