private ArrayList<Integer> processOpenings(ArrayList<Integer> openings) {
		int prev = openings.get(0);
		int current;
		boolean check = false;
		int counter=0; //tellen hoeveel openingen na elkaar komen
		ArrayList<Integer> ret = new ArrayList<Integer>();
		for (int i = 1; i < openings.size(); i++) {
			current = openings.get(i);
			if ((current == prev + 1) || (current == prev + this.squaresX)) {
				counter++;
				check = true;
			} else
				check = false;
			if (!check) {
				ret.add(openings.get(i - counter/2 - 1));
				counter=0;
			}
			prev = current;
		}
		ret.add(openings.get(openings.size() - 1 - counter/2));
		return ret;
	}