LRU Cache (incl. Weighted Variant)

Problem Overview

Implement an LRU (Least Recently Used) cache supporting get and put. The standard variant uses a fixed item-count capacity: get(key) returns the value if present and marks it most recently used; put(key, value) inserts or updates, evicting the least recently used entry when capacity is exceeded. A weighted variant…

• 3 candidate-reported follow-ups — the exact probes interviewers asked, with the trigger for each
• The rest of the problem statement — full requirements, constraints, and edge cases
• Approach and trade-offs — what passing candidates did, and the mistakes that sink people