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Design Twitter
Design Twitter tests whether you can keep a best-so-far structure honest as you go. Interviewers love it because it reveals your priority-based reasoning and your edge-case discipline. The trap is stale entries or unbalanced structures—be clear about what belongs in the heap.
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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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