Code RoomCount palindromic substrings
HardPrep Room Coding #1368

Count palindromic substrings

CodingAlgorithms & data structuresSenior–Staff~30 min

Given a lowercase string s, count the number of palindromic substrings of s (each occurrence at distinct start/end positions counts separately; single characters count). For example 'aaa' has 6: three single 'a', two 'aa', and one 'aaa'. The string length is up to a few thousand.

Implement
count_palindromic_substrings(s: str) → int
Examples
in["aaa"]out6
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 30 min
InputExpectedGot
["aaa"]6not run yetsample