Comment Moderator — detect banned words and return only clean comments using hash lookup-based filtering. Memoization Function — build a wrapper that returns cached result for same inputs without recomputing. Cross the Threshold — find maximum barrier value such that total sum stays above threshold after energy reduction (binary search on answer space). Given a products array, return frequency count sorted by frequency; equal frequency sorted in descending alphabetical order. Shoot the plane problem. How do you measure web performance and what metrics are used? Explain core web performance metrics — LCP, CLS, INP. What root causes lead to poor values for these metrics and how can they be optimized? How would you optimize performance for a page with thousands of images? What types of frontend tests exist beyond unit testing and what are their differences and challenges? What storage options are available in the browser?