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Robinhood Order Book
Also known as: Order Book with Price-Time Priority
Implement an order book with limit/market orders, price-time priority matching, partial fills, and cancellation. Outputs are deterministic and easy to audit.
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Low-Level Design Interview Questions
Low-level design problems test whether you can model a small API, preserve invariants, and choose storage that matches the required operations. Expect recurring shapes like rate limiters, hit counters, tic-tac-toe, file systems, and autocomplete.
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