@Test
public void testFastFree() {

    int maxLength = Integer.MAX_VALUE;
    
    List<Tuple2id> result = recommender.getRecommendation(0, maxLength).getIidxs();
    List<Tuple2id> expected = Arrays.asList(
            tuple(0, 6.0),
            tuple(1, 5.0),
            tuple(2, 4.0),
            tuple(3, 3.0),
            tuple(4, 2.0),
            tuple(5, 1.0)
    );
    
    assertEquals(expected, result);
}