diff --git a/Sprint-2/implement_lru_cache/lru_cache.py b/Sprint-2/implement_lru_cache/lru_cache.py index e69de29..9f3e784 100644 --- a/Sprint-2/implement_lru_cache/lru_cache.py +++ b/Sprint-2/implement_lru_cache/lru_cache.py @@ -0,0 +1,101 @@ +import time + +our_list = [] +lookup_map = {} +limit = 0 + +# `LruCache(limit)` should construct +# an LRU cache which never stores more than `limit` entries. +def LruCache(user_limit): + global limit, our_list, lookup_map + limit = user_limit + our_list = [] + lookup_map = {} + +# * `set(key, value)` should associate `value` with the passed `key`. +def set(key, value): + global our_list, lookup_map + + if key in lookup_map: + old_item = lookup_map[key] + our_list.remove(old_item) + + wrapped_item = { + "key": key, + "value": value, + "tracker": time.time() + } + +#add to list and map + our_list.insert(0, wrapped_item) + lookup_map[key] = wrapped_item + +#if full remove oldest timestamp so last + if len(our_list) > limit: + oldest_item = our_list.pop() + + del lookup_map[oldest_item["key"]] + + +# * `get(key)` should look-up the value previously associated with `key`. +def get(key): + global our_list, lookup_map +#check map instead of for loop + if key in lookup_map: + # find by key + item = lookup_map[key] + + # // tracker to now timestamp updaed + item["tracker"] = time.time() + + #move to front + our_list.remove(item) + our_list.insert(0, item) + + return item["value"] + return None + + +#before i did it this was but was looping over each item and did not +#fit the required complexity +# def get_old(key): +# for item in our_list: +# if item["key"] == key: +# item["tracker"] = time.time() +# our_list.remove(item) +# our_list.insert(0, item) +# return item["value"] +# return None + +#and before tried with an id not timestamp +# tracker_number = 0 + +# def set(key, value): +# global tracker_number, our_list, lookup_map + + +# wrapped_item = { +# "key": key, +# "value": value, +# "tracker": tracker_number +# } + + +# tracker_number += 1 + +# our_list.insert(0, wrapped_item) +# lookup_map[key] = wrapped_item + +# and the loop +# def get_old(key): +# global tracker_number, our_list +# for item in our_list: +# if item["key"] == key: +# item["tracker"] = tracker_number +# tracker_number += 1 + +# our_list.remove(item) +# our_list.insert(0, item) + +# return item["value"] +# return None \ No newline at end of file