# sum_digits Given a non-negative int `n`, return the sum of its digits recursively (no loops). Note that mod (`%`) by `10` yields the rightmost digit (`126 % 10` is `6`), while integer divide (`//`) by `10` removes the rightmost digit (`126 // 10` is `12`). ``` sum_digits(126) -> 9 sum_digits(49) -> 13 sum_digits(12) -> 3 ``` This exercise was taken from [codingbat.com](https://codingbat.com/prob/p163932) and has been adapted for the Python language. There are many great programming exercises there, but the majority are created for Java. ## Starter Code ```python def sum_digits(n: int) -> int: pass result = sum_digits(126) print(result) ``` ## Tests ```python from main import sum_digits def test_sum_digits_1(): assert sum_digits(126) == 9 def test_sum_digits_2(): assert sum_digits(49) == 13 def test_sum_digits_3(): assert sum_digits(12) == 3 def test_sum_digits_4(): assert sum_digits(10) == 1 def test_sum_digits_5(): assert sum_digits(1) == 1 def test_sum_digits_6(): assert sum_digits(0) == 0 def test_sum_digits_7(): assert sum_digits(730) == 10 def test_sum_digits_8(): assert sum_digits(1111) == 4 def test_sum_digits_9(): assert sum_digits(11111) == 5 def test_sum_digits_10(): assert sum_digits(10110) == 3 def test_sum_digits_11(): assert sum_digits(235) == 10 ```