def test_example2(): digits = [1, 0, 9, 9] assert ([1, 1, 0, 0] == plus_one(digits))
def test_example1(): digits = [1, 2, 3] assert ([1, 2, 4] == plus_one(digits))
def test_case2(): digits = [1, 9, 9] assert ([2, 0, 0] == plus_one(digits))
def test_case3(): digits = [9] assert ([1, 0] == plus_one(digits))
def test_case1(): digits = [9, 9] assert ([1, 0, 0] == plus_one(digits))