Question

如何设计实现一个LRU Cache

Answer 1

之前，在LeetCode上看到一个LRU Cache实现的题目，题目描述是这样的：
Design and implement a data structure for Least Recently Used (LRU) cache. It should support the following operations: get and set.
get(key) - Get the value (will always be positive) of the key if the key exists in the cache, otherwise return -1.
set(key, value) - Set or insert the value if the key is not already present. When the cache reached its capacity, it should invalidate the least recently used item before inserting a new item.
简单的说，就是保证基本的get和set的功能的同时，还要保证最近访问(get或put)的节点保持在限定容量的Cache中，如果超过容量则应该把LRU(近期最少使用)的节点删除掉。