Harden LRU cache core
Hard Data Structures arena: hash map plus doubly linked list invariants
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Missing prerequisites: data-structures-easy-lru-cache
A feature flag service needs O(1) reads and evictions under heavy traffic. You are working inside an interview-style data structure lab, and the arena only clears when the result is safe, deterministic, and explainable.
Learn to apply hash map plus doubly linked list invariants in an interview-style data structure lab while explaining the invariant, safety constraints, and hidden edge cases.
- Demonstrates hash map plus doubly linked list invariants
- Handles the visible sample and hidden edge cases
- Keeps output deterministic and explainable
- Avoids unsafe dynamic execution
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