Implement a Size-Aware LRU Cache | Dataford Interview Questions

Implement an LRU cache variant in which each item carries a quantity/size, so capacity is counted by total quantity rather than number of items (otherwise standard LRU).

Asked in the coding round 1 stage. Clarify that eviction continues until total size is within capacity, and that updating an existing key's size can trigger eviction.

Contract

Implement lru_cache_variant(capacity, operations). Operations are ['put', key, value, size] or ['get', key]; return values from get, using -1 for missing keys. Updating a key refreshes recency. Items larger than capacity are not stored. Example: capacity 3, operations [['put','a','A',4],['get','a']] returns [-1].

Constraints

1 <= capacity <= 10^5
1 <= len(operations) <= 1000
Each operation is either ['get', key] or ['put', key, value, size]
Keys are unique strings when stored
1 <= size <= 10^5
Values are strings
An item larger than capacity is not stored

Function Signature

def lru_cache_variant(capacity, operations):

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