Hash Table Internals — Why O(1) is 'Amortized' and What That Means

Staff interviewers sometimes ask you to go deeper on hash table complexity. 'You said amortized O(1) — can you explain what amortized means here?' or 'When would a dict lookup actually be O(n)?' This section gives you the depth to answer confidently, and the DE-specific framing for why it matters in production pipelines. Hash Collisions — The O(n) Worst Case