Implement a Level-Aware Expiring Inventory Store
Company: Optiver
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: medium
Interview Round: Take-home Project
Implement an inventory store with levels, weights, timestamps, and expiration. `store` adds an item. `retrieve(timestamp)` returns and removes the highest-weight active item from the highest level where at least 50 percent of all items ever stored on that level are still active.
Implement:
```python
def process_inventory_operations(operations: list[list]) -> list[str]:
pass
```
Return one item id for each retrieve, or an empty string if none is eligible.
Quick Answer: Practice a Optiver coding interview problem focused on implement a level-aware expiring inventory store. The prompt emphasizes edge cases, clean implementation, and verifiable test behavior without revealing the solution.
Process store and retrieve operations with level eligibility, expiration, and highest-weight retrieval.
Examples
Input: {"operations":[["store","a",1,5,0,None],["retrieve",1]]}
Expected Output: ["a"]
Explanation: Basic retrieval.
Input: {"operations":[["retrieve",1]]}
Expected Output: [""]
Explanation: Empty store.