I think LRU does NOT work with this trick, because there's no easy way to "move-to-front" in O(1) time.
The article mentions Java's LinkedHashMap, which actually can do LRU. But as the name implies, they rely on a linked list, where move=to-front is natural.
But this superpower does not come for free: a Java-style linked hash map will use more memory than the technique described in the article.
The article mentions Java's LinkedHashMap, which actually can do LRU. But as the name implies, they rely on a linked list, where move=to-front is natural.
But this superpower does not come for free: a Java-style linked hash map will use more memory than the technique described in the article.