LRU Cache

Internal

• Caches
• The Optimal Caching Problem

Overview

The Least Recently Used caches are justified by the Bélády Theorem

An implementation where get() is O(1) and put() is O(n): Playground LRUCache O(n)

An implementation where both get() and put() are O(1): Playground LRUCache O(1)

The idea is to maintain the keys in a map (O(1)) for retrieval, but the time ordering is maintained implicitly in the structure of a double-linked list that can be manipulated in O(1): Playground LRUList