Code RoomCount pattern occurrences
MediumPrep Room Coding #961

Count pattern occurrences

CodingAlgorithms & data structuresMid–Senior~20 min

Given a string s of lowercase letters and an integer k (1 <= k <= len(s) <= 10^5), let p be the prefix s[0:k]. Return the number of positions in s where p occurs as a contiguous substring, counting OVERLAPPING occurrences. If k is 0 or exceeds len(s), return 0.

Implement
count_good_substrings_period(s: str, k: int) → int
Examples
in["ababab",2]out3
What 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
InputExpectedGot
["ababab",2]3not run yetsample