Katkat

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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 8611–8640 of 9403 results

  • Two SigmaMediumQuantitative Researcher
    Linear Interpolator with Extrapolation

    This question evaluates understanding of piecewise linear interpolation and extrapolation, numerical robustness with floating-point values, and algorithmic competencies such as sorting and efficient query location for large datasets.

    Coding & AlgorithmsTechnical Screen
  • Two SigmaMediumSoftware Engineer
    Match Limit Orders with Price-Time Priority

    Implement a limit order matching engine adhering to price-time priority (FIFO), resting-order execution pricing, and partial fill mechanics.

    Coding & AlgorithmsTechnical ScreenHeapData StructuresSimulation
  • Two SigmaEasyData Scientist
    Match readings with latest same-city humidity

    This question evaluates the ability to align and join time-ordered sensor data by key, testing skills in time-series merging, per-key state management, and handling absent matches.

    Coding & AlgorithmsTechnical Screen
  • Two SigmaMediumSoftware Engineer
    Maximize Capital by Completing at Most k Projects

    This question evaluates algorithmic problem-solving and optimization skills within the Coding & Algorithms domain, focusing on selection under resource and operation constraints and reasoning about time and space complexity.

    Coding & AlgorithmsTechnical Screen
  • Two SigmaHardData Scientist
    Maximum-Product Simple Path in a Complete Directed Graph

    This question evaluates skills in graph algorithms, multiplicative path optimization, and combinatorial dynamic programming, testing competency in reasoning about simple paths and product-based scoring in directed weighted graphs.

    Coding & AlgorithmsOnsite
  • Two SigmaHardData Scientist
    Merge Two Sorted Lists

    This problem tests your ability to manipulate linked list pointers to merge two sorted sequences efficiently without allocating extra space for new nodes.

    Coding & AlgorithmsTechnical ScreenLinked ListsPointersRecursion
  • Two SigmaHardData Scientist
    Merge two sorted linked lists

    This problem tests your ability to manipulate linked list pointers to merge two sorted structures in-place, focusing on space optimization and handling edge cases.

    Coding & AlgorithmsTechnical ScreenLinked ListsPointersIn-place
  • Two SigmaMediumData Scientist
    Perform no-intercept linear regression from two datasets

    This question evaluates linear regression modeling, numerical linear algebra (normal equations and stable factorization methods), regularization, R² interpretation, and data-preprocessing/validation skills within the Machine Learning domain for a Data Scientist role.

    Machine LearningOnline Assessment
  • Two SigmaHardData Scientist
    Predict Citi Bike Demand at a Specific NYC Station

    This question evaluates time-series forecasting, demand estimation, and ML system-design competencies, focusing on problem framing, handling censored observations, data integration, model selection, and evaluation under operational constraints.

    ML System DesignTechnical Screen
  • Two SigmaMediumData Scientist
    Predict Stock Prices from Google Search Data

    This question evaluates a candidate's competency in time-series and cross-sectional predictive modeling, alternative-data feature engineering, and rigorous validation to prevent temporal leakage within the Machine Learning domain.

    Machine LearningTechnical Screen
  • Two SigmaHardData Scientist
    Predict a Company's Stock Price from Six Years of Web Search Logs

    This question evaluates proficiency in feature engineering and time-series forecasting from large-scale event logs, including entity linking, aggregation and normalization, handling non-stationarity and drift, and model selection and validation for predicting a given company's stock price.

    Machine LearningTechnical Screen
  • Two SigmaHardData Scientist
    Predict bike demand and avoid overfitting

    This question evaluates time-series forecasting, feature engineering, awareness of data leakage risks, model evaluation choices, and overfitting prevention competencies within the Machine Learning domain applied to demand prediction.

    Machine LearningTechnical Screen
  • Two SigmaHardData Scientist
    Predicting Stock Prices from Twitter Data

    This question evaluates competency in ML system design for integrating NLP-derived signals from social media with time-series financial modeling, including feature extraction, timestamp alignment, and handling low signal-to-noise ratios.

    ML System DesignTechnical Screen
  • Two SigmaMediumData Scientist
    Return sorted values after quadratic transform

    This problem tests your ability to efficiently transform elements in a sorted array using a quadratic function and merge them back into a single sorted array in linear time.

    Coding & AlgorithmsTechnical ScreenArraysTwo PointersSorting
  • Two SigmaHardData Scientist
    Slopes of y-on-x vs x-on-y Regression: Relationship and When They Are Equal

    This question evaluates understanding of simple OLS linear regression estimators, moment-based expressions for slopes, the relationship between y-on-x and x-on-y fitted slopes, and how correlation and variable scaling influence coefficient values.

    Machine LearningTechnical Screen
  • Two SigmaMediumSoftware Engineer
    Solve capital selection and grid escape

    This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Solve capital selection and grid escape states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Coding & AlgorithmsOnsite
  • Two SigmaMediumMachine Learning Engineer
    Solve tree partition and IPO allocation

    This question evaluates algorithmic problem-solving skills in tree processing and allocation simulations, specifically assessing understanding of subtree-sum computation for tree partitioning and deterministic round-robin allocation logic for IPO-style share distribution, along with appropriate data structure selection and correctness under edge cases. It is commonly asked in the Coding & Algorithms domain because it measures practical application-level implementation and the ability to analyze time and space complexity rather than purely conceptual proof.

    Coding & AlgorithmsOnline Assessment
  • Two SigmaMediumData Scientist
    Why Is the Sample Mean Approximately Normal for Large Samples?

    This question evaluates understanding of the Central Limit Theorem and asymptotic statistical reasoning, including recognition that the standardized sample mean (equivalently the standardized sum) becomes approximately normal and how that fact underpins inference such as confidence intervals.

    Machine LearningTechnical Screen
  • Two SigmaHardData Scientist
    Why Use a t-Statistic?

    This problem tests your conceptual understanding of the t-statistic, specifically how sample parameters influence its value and how it bridges the gap between estimation and hypothesis testing.

    Statistics & MathTechnical ScreenStatisticsHypothesis TestingQuantitative Finance
  • Two SigmaEasyData Scientist
    Why is the t-statistic useful

    This question tests the candidate's conceptual understanding of the t-statistic, specifically its role in hypothesis testing when population parameters are unknown.

    Statistics & MathTechnical ScreenStatisticsHypothesis TestingInference
  • Two SigmaHardData Scientist
    Why use the t-statistic?

    This question tests the conceptual understanding of the t-statistic, specifically why it is used instead of the Z-statistic when population parameters are unknown and how it accounts for uncertainty in sample variance.

    Statistics & MathTechnical ScreenStatisticsHypothesis TestingT-Distribution
  • UberMediumSoftware Engineer
    Aligning Two Teams with Conflicting Priorities and Learning from a Mistake

    Two senior behavioral prompts: describe bringing two teams with conflicting priorities into alignment to deliver an important project, and a mistake you made, the feedback you received and how you closed the gap. It assesses cross-team influence, conflict resolution and growth.

    Behavioral & LeadershipOnsite
  • UberMediumData Scientist
    Analyze Cancellation Change with Statistics

    This question evaluates statistical inference for binary outcomes, regression adjustment for confounding, experiment design and power analysis, and nonparametric uncertainty estimation using bootstrapping, and is targeted at Data Scientist roles within the Statistics & Math domain.

    Statistics & MathTechnical Screen
  • UberEasyMachine Learning Engineer
    Analyze sales with groupby

    This question evaluates proficiency in data manipulation and analytics using pandas, specifically the ability to join relational tables and apply groupby aggregations to compute business metrics like total sales, average sales per order, and completion rates.

    Coding & AlgorithmsTechnical Screen
  • UberMediumSoftware Engineer
    Answer Common Behavioral Questions

    This question assesses the candidate's ability to navigate professional conflict and technical disagreements while maintaining constructive relationships and project momentum.

    Behavioral & LeadershipOnsiteBehavioralConflict ResolutionLeadership
  • UberHardSoftware Engineer
    Answer Repeated Shortest Increasing-Path Queries

    Preprocess shortest strictly increasing grid paths for repeated target queries, with deterministic BFS ties, predecessor reconstruction, and memory trade-offs.

    Coding & AlgorithmsOnsite
  • UberMediumMachine Learning Engineer
    Answer leadership questions on tradeoffs and collaboration

    This set of behavioral leadership questions evaluates leadership competencies including trade-off decision-making, mentorship, cross-functional collaboration, roadmap prioritization, and conflict resolution for a Machine Learning Engineer within the Behavioral & Leadership domain, focusing on practical application through recounting real project experiences. These prompts are commonly asked to probe both conceptual understanding of trade-offs and organizational dynamics and the practical application of influence, communication, and judgment when aligning stakeholders and prioritizing work.

    Behavioral & LeadershipOnsite
  • UberHardData Scientist
    Apply instrumental variables under interference

    This question evaluates understanding of causal inference with instrumental variables in the presence of interference, testing skills in defining units and aggregation levels for market‑level spillovers, articulating IV assumptions (relevance, exclusion restriction, independence, monotonicity), and formulating estimation frameworks such as two‑stage least squares. Commonly asked in Statistics & Math interviews for data scientist roles because networked marketplaces invalidate simple A/B tests, it sits in the econometrics/causal inference domain and primarily assesses practical application of IV methods while requiring conceptual understanding of identification, robustness diagnostics, and sensitivity analysis.

    Statistics & MathTechnical Screen
  • UberMediumSoftware Engineer
    Assign Meetings to the Minimum Number of Rooms

    Assign meetings to the minimum number of rooms using deterministic room ID allocation, returning the room assigned to each meeting in original input order.

    Coding & AlgorithmsOnsiteheapintervalssorting
  • UberMediumSoftware Engineer
    Behavioral: your most complex project, a conflict you resolved, and a failure

    Three hiring-manager behavioral questions: describe your most complex project, a conflict you resolved, and a failure you owned. Answers are judged on STAR structure, personal ownership, concrete and measurable results, a fair account of other people's views, and lessons that were actually applied later.

    Behavioral & LeadershipOnsite