Anthropic
5 questions · Coding · System design · Behavioral
Find the length of the longest substring without repeating characters.
CodingApproachSliding window with a set/last-seen map; advance the right edge, shrink the left on a repeat.
They look forTwo-pointer/sliding-window fluency and off-by-one care.
Return the k-th largest element in an unsorted array.
CodingApproachA size-k min-heap, or quickselect for average O(n); discuss the trade-offs.
They look forHeap vs. selection trade-offs and awareness of average vs. worst case.
Design a rate limiter for a public API.
System designApproachCompare token bucket vs. sliding window, where state lives (per-node vs. Redis), and behavior under bursts.
They look forAlgorithm choice, distributed state, and failure/consistency trade-offs.
Design a serving layer for large-model inference under load.
System designApproachBatching, queuing, autoscaling GPUs, timeouts, and graceful degradation.
They look forReasoning about latency/throughput trade-offs in ML infra.
Tell me about a time you weighed shipping speed against safety/quality.
BehavioralApproachShow principled trade-off thinking and how you decided.
They look forJudgment and care — central to the company’s mission.
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