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Snack Bin Iterator — Flatten Nested Lists
Also known as: Flatten Nested List Iterator
This one is all about maintaining a clear stack meaning as you process input. Interviewers love it because it reveals your stack invariants and your edge-case discipline. Keep the stack invariant explicit; if it breaks, everything downstream breaks too.
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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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