@Test
    public void testEasy8() throws Exception {
        String start = "";
        String end = "";
        String[] words = {};
        Set<String> dict = Utils.stringArrayToSet(words);

        WordLadderII wordLadderII = new WordLadderII();
        List<List<String>> result = wordLadderII.findLadders(start, end, dict);

        Utils.printListListString(result);
    }