C++ Implementation of LRU & LFU Cache

Sat, 04 Sep 2021 17:22:00 -0400

LRU (Least Recently Used) Cache

Referring to LeetCode Q146 https://leetcode.com/problems/lru-cache/

LRUCache(int capacity) Initialize the LRU cache with positive size capacity.
int get(int key) Return the value of the key if the key exists, otherwise return -1.
void put(int key, int value) Update the value of the key if the key exists. Otherwise, add the key-value pair to the cache. If the number of keys exceeds the capacity from this operation, evict the least recently used
The functions get and put must each run in O(1) average time complexity.

To satisfy the O(1) average time complexity for get and put,