LFU Cache II

Problem Design and implement a data structure for a Least Frequently Used (LFU) cache. It should support two operations: get(key): Retrieve the current value associated with key. If the key exists, increment its usage frequency and return the value. If the key does not exist, return -1. put(key, value): Insert or update the key with the given value. When the key is already present, update its value and increment its frequency. When the cache has reached its capacity, evict…