Find longest substring with ≥k repeats
Company: TikTok
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: hard
Interview Round: Technical Screen
Overview: This question evaluates proficiency with string-processing techniques and character frequency analysis, focusing on algorithmic skills in the Coding & Algorithms domain. It is commonly asked to assess algorithmic reasoning about constraint handling, edge cases, and efficiency, and is positioned at the practical application level rather than purely conceptual understanding.