Squirrel Nut Storage Tracker

An OOP simulation OA: model cone-shaped hiding locations whose level capacities grow Fibonacci-style, then support hiding nuts (deepest-level-first, with expiry) and retrieving them under a layered weight/percentage rule with a fall-down refill mechanic. Heavy on careful rule implementation. Requirements Implement the SquirrelResearch class. Operations carry globally-ever-increasing timestamps (seconds since epoch, float). Weights are floats in grams. init(locations: dict[str, int]) — locations maps a location id to its number of levels. Levels are cone-shaped and grow per the Fibonacci sequence; e.g. a 3-level location holds 6 nuts: 1 at the deepest level, 2 in the middle, 3 at the top. HideNut(timestamp, location_id, nut_id, nut_weight, time_to_expire) -> bool — hide a nut. Fill from the deepest level upward; only move to the next level once the current one is full. nut_id must be globally unique among hidden nuts. Fail if the location is full/invalid. The nut expires immediately after timestamp + time_to_expire. RetrieveNuts(timestamp, location_id, max_squirrel_capacity_in_nuts) -> list[str] — retrieve up to a capacity of nuts, returning their ids in retrieval order. Retrieval rules: Retrieve by level starting from the topmost level that has nuts; within a level, heavier nuts first, ties broken by smallest id alphabetically. If the topmost occupied level is under 50% of its capacity, the next level down also becomes reachable, and the squirrel prefers heavier nuts from there. Whenever a nut is taken from a level that isn't the topmost occupied level, the lightest nut from the level above falls down into the freed slot. Expired nuts that get retrieved are immediately discarded (not returned). Retrieved/discarded nuts are removed; a nut_id may be reused afterward. Fail (empty list) if the location is empty/invalid. Notes The Fibonacci level sizing starts "from the 3rd digit" — confirm the per-level capacities (1, 2, 3, 5, …) against the worked example (3 levels → 1+2+3 = 6). The 50%-reachability rule plus the fall-down refill is where most candidates lose correctness; model each level as an ordered structure keyed by (weight, id) and re-evaluate reachability after each removal. Expiry is checked at retrieval time against the retrieval timestamp. Preparation Implement per-level ordered containers (by weight, then id) and the deepest-first fill; then layer in the 50% reachability and the fall-down refill. Test expiry-on-retrieve, the under-50% cross-level pull, and tie-breaking by id as separate cases.