Challenge 164 - Unusual Subtraction

challenge_164.md

Challenge 164 - Unusual Subtraction

Create a function that subtracts 1 from n (unless it ends in 0) k number of times. If n ends in 0, remove the 0.

To illustrate

n = 22
k = 3

This means our number is 22 and we have to repeat the algorithm three times. 22 does not end in 0 so we continue subtracting 1.

22 - 1 = 21
k = 1
21 - 1 = 20
k = 2

Now 20 ends in 0, so we can remove it. We get 2; k = 3. The algorithm ends there because we applied it three times.

N:  K:
22
21  1
20  2
2   3

Examples

unusual_subtraction(540, 5) ➞ 50

unusual_subtraction(1000000000, 9) ➞ 1

unusual_subtraction(42023110, 10) ➞ 4201

challenge_tests.py

import unittest


def unusual_subtraction(n: int, k: int) -> int:
    return 0  # Put your code here!!!


class Test(unittest.TestCase):
    def test_1(self):
        self.assertEqual(unusual_subtraction(78, 9), 7)

    def test_2(self):
        self.assertEqual(unusual_subtraction(540, 5), 50)

    def test_3(self):
        self.assertEqual(unusual_subtraction(1000000000, 9), 1)

    def test_4(self):
        self.assertEqual(unusual_subtraction(420, 4), 4)

    def test_5(self):
        self.assertEqual(unusual_subtraction(42023110, 10), 4201)

    def test_6(self):
        self.assertEqual(unusual_subtraction(88888888, 50), 883)


if __name__ == "__main__":
    unittest.main()

credits.md

Found on Edabit: Unusual Subtraction