public String[] getAlphabet(Automaton automaton) {
		ArrayList list = new ArrayList();
		Transition[] transitions = automaton.getTransitions();
		for (int k = 0; k < transitions.length; k++) {
			FSATransition transition = (FSATransition) transitions[k];
			String label = transition.getLabel();
			if (!label.equals("") && !list.contains(label)) {
				list.add(label);
			}
		}
		return (String[]) list.toArray(new String[0]);
	}