Distinct k-length substrings
Given a string s and an integer k, return the number of distinct substrings of s that have exactly length k. If k is greater than len(s) or k <= 0, return 0. For example, in "banana" the length-2 substrings are "ba", "an", "na", "an", "na", of which 3 are distinct. The string can be long, so the intended solution slides a fixed-size window (a rolling hash being one classic way to do it).
Implement
distinct_substrings_of_len_k(s: str, k: int) → intExamples
in
["banana",2]out3What a strong answer looks like
State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.
0:00 of about 20 min
solution.py
InputExpectedGot
["banana",2]3not run yetsample