Start by clarifying the data format (timestamps, event types) and the definition of 'time elapsed' (e.g., difference between two specific events). Then outline a general algorithm: sort events by timestamp, identify the two events, and compute the difference. Finally, discuss implementation details like handling time zones, missing data, and scalability.
Pro tip: Mention that you would validate the result by checking for negative durations or outliers, and consider using efficient data structures (e.g., heaps) if the dataset is large and you need to find the closest pair of events.
Ask about the data schema (e.g., timestamps in what format, event identifiers) and the exact definition of 'time elapsed' (e.g., between two specific events, or between any two events of different types).
For a single pair of events, simply subtract timestamps. For multiple pairs or to find the minimum/maximum elapsed time, sort events by timestamp and scan, or use a heap for streaming data.
Address time zones, daylight saving, missing events, duplicate timestamps, and events out of order. Ensure the difference is non-negative and consider precision (e.g., milliseconds).
Write pseudocode or describe code. Discuss time/space complexity (e.g., O(n log n) for sorting) and optimizations like using a min-heap for large datasets or parallel processing.
Suggest testing with sample data, checking for negative durations, and verifying against known cases. Mention monitoring in production for anomalies.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.