This notebook was prepared by Donne Martin. Source and license info is on GitHub.
Refer to the Solution Notebook. If you are stuck and need a hint, the solution notebook's algorithm discussion might be a good place to start.
class Solution(object):
def longest_substr(self, string, k):
# TODO: Implement me
pass
The following unit test is expected to fail until you solve the challenge.
# %load test_longest_substr.py
import unittest
class TestSolution(unittest.TestCase):
def test_longest_substr(self):
solution = Solution()
self.assertRaises(TypeError, solution.longest_substr, None)
self.assertEqual(solution.longest_substr('', k=3), 0)
self.assertEqual(solution.longest_substr('abcabcdefgghiij', k=3), 6)
self.assertEqual(solution.longest_substr('abcabcdefgghighij', k=3), 7)
print('Success: test_longest_substr')
def main():
test = TestSolution()
test.test_longest_substr()
if __name__ == '__main__':
main()
Review the Solution Notebook for a discussion on algorithms and code solutions.