Implement In-Memory Key-Value Store With Expiration
Design and implement an in-memory key-value store that supports basic operations (get, put, delete) with automatic key expiration based on TTL (time-to-live). The implementation should efficiently handle expired key cleanup and provide O(1) average time complexity for core operations.
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Late February, 2026
Mid-level
Problem starts with a basic statement of designing a cache where an entry has an expiry. As a candidate, you are expected to clarify requirements (like capacity, datatype, single/multi threaded env, eviction policy..) Code the basic version, complie and test with some examples. Follow ups after basic functionality: - Changes if its a distributed system? - What eviction policy to use?
Early January, 2026
Senior
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