Master Intelligent Cache Design: Implementing LFU Through LRU Principles

LFU (Least Frequently Used) cache is a sophisticated eviction policy that balances frequency and recency—critical for real-world systems managing memory under constraints. This guide demonstrates how leveraging LRU (Least Recently Used) concepts enables an elegant O(1) implementation using hash maps and doubly linked lists, making it essential for system design interviews and backend optimization. Understanding this pattern transforms cache management from theoretical concept into a practical skill for building high-performance applications.