Resumable List/File Iterator

Problem Overview

Design and implement a resumable iterator — an iterator that supports pausing and resuming from a saved checkpoint. The iterator must expose three core methods: next() (returns the next element), getState() (returns a serializable state object representing the current position), and setState(state) (restores the iterator to a previously saved state).…

• 7 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