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5 questions · Coding · System design
Find two numbers in an array that sum to a target and return their indices.
CodingApproachOne pass with a hash map of value → index; for each x, check whether target − x was already seen.
EvaluatesWhether you move from the brute-force O(n²) to a clean O(n) hash-map solution and reason about edge cases.
Determine whether a string of brackets is balanced.
CodingApproachPush opens onto a stack; on a close, pop and match. Empty stack at the end means valid.
EvaluatesStack intuition and handling of mismatched/empty edge cases.
Design a URL shortener (like TinyURL).
System designApproachTalk through the API, a hash/base-62 key scheme, storage and read/write ratio, caching hot links, and redirects.
EvaluatesScoping, key generation, read-heavy scaling, and caching decisions.
Tell me about a time you disagreed with a teammate or manager.
BehavioralApproachUse STAR: the situation, your reasoning, how you disagreed respectfully and reached a decision, and the result.
EvaluatesCommunication, judgment, and whether you can disagree-and-commit without drama.
Tell me about a time you failed and what you changed afterward.
BehavioralApproachPick a real failure, own it without blaming others, and show the concrete lesson you applied later.
EvaluatesSelf-awareness, accountability, and growth.
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