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Interview Questions
Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.
- 9403
- Questions
- 546
- Companies
- 11
- Topics
- 8
- Languages
Showing 6661–6690 of 9403 results
- OtherMediumSoftware EngineerDesign a Task Scheduler
Design a durable task scheduler with due-time indexing, atomic claims, worker leases, retry states, recurring occurrences, and clear duplicate-delivery semantics.
System DesignOnsite - OtherHardData ScientistDesign an A/B test with guardrails
This question evaluates a data scientist's skills in experimental design, hypothesis testing, statistical power and sample-size calculation, randomization and contamination control, pre-registration planning, and multiplicity adjustment for A/B testing.
Analytics & ExperimentationOnsite - OtherMediumData ScientistDesign anomaly detection and handle imbalanced logistic regression
Design a fraud detection setup for 50M transactions at a 0.4% fraud rate: a supervised logistic regression model plus an unsupervised anomaly detector for new merchants with no labels. Cover time-based splits, delayed labels, imbalance, calibration, and a cost-based threshold where a missed fraud costs far more than a false alarm.
Machine LearningTechnical Screen - OtherHardData ScientistDesign metrics and experiment
This question evaluates a candidate's competency in experimental design, success-metric definition, event instrumentation, causal inference for heterogeneous treatment effects, and statistical power and sample-size calculations for subscription-product analytics.
Analytics & ExperimentationTechnical Screen - OtherMediumData ScientistDesign metrics resilient to data quality
This question evaluates the ability to design robust data-quality metrics and apply SQL window-function techniques for deduplication and time-windowed completeness calculations, focusing on quantifying how ingestion delays, duplicates, and negative amounts can bias payment metrics.
Analytics & ExperimentationTechnical Screen - OtherMediumData ScientistDiagnose and fix linear regression violations
Work through an OLS model on 10,000 observations: state the Gauss-Markov assumptions, show why residuals are orthogonal to the predictors, and handle three correlated predictors. Decide which violations break unbiasedness versus only inference, and what fixes apply.
Statistics & MathOnsite - OtherMediumSoftware EngineerExplain How You Use and Validate AI at Work
Explain practical AI use at work through a concrete task, bounded prompts, independent validation, a corrected failure, and accountable engineering decisions.
Behavioral & LeadershipOnsite - OtherMediumSoftware EngineerExplain RF/analog IC interview fundamentals
This interview question evaluates engineering fundamentals, trade-offs, examples, pitfalls, and operational implications in a realistic interview setting. A strong answer for Explain RF/analog IC interview fundamentals states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Software Engineering FundamentalsOnsite - OtherEasySoftware EngineerFewest Days to Read a Book When Chapters Cannot Be Split Across Days
Given the reading time available on each day and the time each chapter of a book takes, find the fewest days needed to read every chapter in order when a chapter can never be split across days, or report that the book cannot be finished. It tests simulation with per-day capacity, ordering constraints, and impossible cases.
Coding & AlgorithmsOnline Assessment - OtherMediumSoftware EngineerFilter Logs by an Ordered Severity Threshold
Filter structured logs by an ordered minimum severity, preserving threshold-and-higher records while handling empty and unknown levels under an explicit contract.
Coding & AlgorithmsOnsite - OtherMediumData ScientistHandle unprofessional, prescriptive interviewers
This question evaluates interpersonal communication, conflict management, stakeholder negotiation, time management, and the ability to succinctly surface technical and data-quality risks during a constrained SQL screening, reflecting competencies relevant for data scientists in collaborative settings.
Behavioral & LeadershipTechnical Screen - OtherEasyData ScientistHow would you measure and experiment on harmful content?
This question evaluates a data scientist's competency in measuring and experimenting on harmful user-generated content, focusing on severity quantification, metric selection, and randomized experiment design within the analytics and experimentation domain.
Analytics & ExperimentationTechnical Screen - OtherMediumData ScientistImplement KNN from scratch
This question evaluates understanding of the k-Nearest Neighbors algorithm, distance metrics (Euclidean and cosine), tie-breaking with class priors, weighted voting, complexity analysis, and scalability strategies, testing competencies in algorithm implementation, model behavior, and computational trade-offs.
Coding & AlgorithmsOnsite - OtherMediumMachine Learning EngineerImplement Linear Regression Training
This question evaluates understanding of linear regression, mean squared error loss, gradient computation, parameter updates, and proficiency with vectorized numerical operations used in batch gradient descent.
Coding & AlgorithmsOnsite - OtherHardSoftware EngineerImplement a multi-button click detector
This question evaluates competency in real-time event stream processing, per-button state management, and timing-based classification of input events such as distinguishing single versus long presses.
Coding & AlgorithmsTechnical Screen - OtherMediumData ScientistImplement multiplication without using the multiplication operator
This question evaluates proficiency in bitwise arithmetic, integer overflow semantics, sign handling, and algorithmic efficiency for implementing multiplication without using multiplication or division operators.
Coding & AlgorithmsTechnical Screen - OtherEasySoftware EngineerLowest Common Ancestor in an Explicit Binary Tree
Find the lowest common ancestor in a binary tree using explicit child arrays, including identical targets, ancestor targets, and deep trees.
Coding & AlgorithmsOnline Assessment - OtherMediumAnalytics EngineerMaintain Entry Numbers with Incremental Loads and Historical Backfills
Design incremental per-context entry numbering with idempotent state, contiguous-gap backfills, and correct handling of interleaved late events.
System DesignTechnical Screen - OtherMediumAnalytics EngineerNumber Entries Within Each Conversation
Assign one-based entry numbers per conversation using timestamp and identifier ordering in a PostgreSQL window-function query.
Data Manipulation (SQL/Python)Technical Screen - OtherMediumQuantitative ResearcherOptimal Stopping with a Ten-Sided Die and a Reset
Derive optimal stopping thresholds for a fair ten-sided accumulation game, then account for the continuation value of a one-time zero reset.
Statistics & MathTechnical Screen - OtherHardData ScientistPredict job changes month by month
This question evaluates competency in discrete-time survival modeling and end-to-end predictive system design, encompassing feature engineering, label/hazard formulation, leakage prevention, model evaluation, fairness assessment, and experimentation for production machine learning.
Machine LearningOnsite - OtherMediumData ScientistProve reservoir sampling correctness
This question evaluates randomized and streaming algorithm skills, including mastery of reservoir sampling, induction-based correctness proofs, probability reasoning, and complexity analysis for sampling under strict memory constraints.
Coding & AlgorithmsOnsite - OtherMediumSoftware EngineerReturn the k-th row of Pascal-like triangle
This question evaluates combinatorics, array manipulation, and space-efficient algorithm design by requiring computation of a specific row of Pascal’s triangle without constructing the full triangle.
Coding & AlgorithmsOnline Assessment - OtherMediumData ScientistSeparate demand from supply for jeans
This question evaluates a data scientist's ability to perform data-driven diagnostics, funnel-metric construction, quantitative decision-rule design, and experimentation planning to distinguish demand-side from supply-side constraints in a marketplace jeans category.
Analytics & ExperimentationOnsite - OtherMediumData ScientistSimulate via inverse transform and Gibbs
This question evaluates understanding of random variate generation and Markov chain Monte Carlo techniques, specifically inverse-transform sampling for the Logistic(μ,s) distribution and Gibbs sampling for a bivariate joint density, testing competency in probability theory, distribution properties, and statistical computing within the Statistics & Math domain. It is commonly asked to assess the ability to derive inverse CDFs and full conditional distributions, verify sample correctness with goodness-of-fit and convergence diagnostics, and reason about sample size, burn-in, and thinning, reflecting a mix of conceptual understanding and practical application.
Statistics & MathOnsite - OtherMediumSoftware EngineerSolve a Set of Probability and Quantitative Reasoning Problems
Work through fourteen quantitative interview problems covering probability, counting, expectation, algebra, logical constraints, and rate reasoning. Each result should be auditable, use the correct sample space, and state any interpretation that affects the calculation.
Statistics & MathOnline Assessment - OtherMediumData ScientistSolve window-function SQL without joins
This question evaluates proficiency with SQL window functions, including running and cumulative sums, LAG/forward-fill event logic, ranking functions (RANK/DENSE_RANK/ROW_NUMBER), tie-breaking strategies, and temporal date arithmetic for payments and subscription events.
Data Manipulation (SQL/Python)Technical Screen - OtherMediumSoftware EngineerSpreadsheet Formulas, Dependencies, and Circular References
Implement spreadsheet formulas with dependency updates, repeated references, unset cells, and cycle detection that recovers after formulas change.
Coding & AlgorithmsOther - OtherMediumSoftware EngineerTest Severity Filtering with Contract-Distinguishing Cases
Test severity filtering with independent expected results, inclusive boundaries, misleading message text, missing fields, empty records, and preserved order and duplicates.
Software Engineering FundamentalsOnsite - OtherEasySoftware EngineerTrack Workers, Sessions, Promotions, and Bonus Pay
Implement worker sessions, current metadata, promotions, ordered filtering, and time-clipped compensation with historical rates and non-stacking double-pay intervals.
Coding & AlgorithmsOnline Assessment