@Override
	public List<StringBuffer> printState() {
		List<StringBuffer> wState = new ArrayList<StringBuffer>();
	        for (int i = 0; i < n; i++) {
	        	StringBuffer temp = new StringBuffer();
	            for (int j = 0; j < n; j++) {
	                if (j < queenPositions.size() && queenPositions.get(j) == i) {
	                    temp.append("Q");
	                } else {
	                	temp.append("_");
	                }
	                temp.append(",");
	            }
	            temp.append("\n");
	           wState.add(temp);
	        }
	        return wState;
	}