def test2(): assert digit_at_index(13) == 1 assert digit_at_index2(13) == 1
def test12(): assert digit_at_index(-10) == -1 assert digit_at_index2(-10) == -1
def test11(): assert digit_at_index(-1) == -1 assert digit_at_index2(-1) == -1
def test10(): assert digit_at_index(0) == 0 assert digit_at_index2(0) == 0
def test1(): assert digit_at_index(5) == 5 assert digit_at_index2(5) == 5
def test3(): assert digit_at_index(19) == 4 assert digit_at_index2(19) == 4