}

    @Test
    public void testPerf() throws IOException {
        List<String[]> data = new ArrayList<>();
        String k = null;
        for (String line : Files.readAllLines(Paths.get("src/test/resources/dag.txt"))) {
            if (line.startsWith("\t")) {
                data.add(new String[] {k, line.trim()});
            } else {
                k = line;
            }
        }
        Collections.shuffle(data);