def test_issorted(self):
self.assertTrue(Backtrack.issorted([1, 2, 3, 4]))
self.assertTrue(Backtrack.issorted([3, 2, 1], reverse=True))
self.assertFalse(Backtrack.issorted([1, 2, 4, 3]))
self.assertFalse(Backtrack.issorted([3, 1, 2], reverse=True))
