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 241–270 of 781 results

  • CitibankMediumData Scientist
    Compute expected payoff of reroll dice game

    This question evaluates understanding of probability theory and expected-value computation in stopping-time processes, including conditioning and infinite-series reasoning, and also tests modeling of per-trial costs and break-even analysis.

    Statistics & MathOnline Assessment
  • CitibankMediumData Scientist
    Price options and bonds via binomial no-arbitrage

    This question evaluates competence in no-arbitrage pricing, risk-neutral valuation, early-exercise features of American versus European options, and short-rate tree bond valuation within the Statistics & Math domain.

    Statistics & MathOnline Assessment
  • CodeiumMediumSoftware Engineer
    Find the third-largest word by length

    This question evaluates proficiency in string and array manipulation, ordering by key metrics (string length), and handling tie-breaking via stable ordering, situated in the Coding & Algorithms domain.

    Coding & AlgorithmsOnline Assessment
  • CoinbaseMediumSoftware Engineer
    Build Task Management Through Records, Search, Assignment, and Completion

    Implement an in-memory task management system that tracks task lifecycles, assignments, and deadlines with efficient indexing and querying. Tests data structure design, state management, and multi-field sorting.

    Software Engineering FundamentalsOnline Assessmentdata-structureshash-tablesorting
  • CoinbaseEasySoftware Engineer
    Clarify CodeSignal partial credit and score access

    This question evaluates understanding of how multi-level coding assessments allocate partial credit for test cases and compute aggregate scores across levels on an online assessment platform, testing competency in assessment logistics and test platform mechanics.

    Behavioral & LeadershipOnline Assessment
  • CoinbaseHardSoftware Engineer
    Design a Timestamped Cloud Credit Ledger with Rebates, Merges, and History

    Design an in-memory cloud credit ledger that processes top-ups, charges with delayed deterministic rebates, account merges with canonical alias resolution, historical balance lookups, and spending leaderboards.

    Software Engineering FundamentalsOnline AssessmentData StructuresDesignHeap
  • CoinbaseHardSoftware Engineer
    Design a bank account ledger

    A complete take-home system-design walkthrough for a bank account ledger service: APIs and data model, an immutable double-entry ledger for auditability, ACID single-account updates and atomic multi-account transfers, idempotency and exactly-once effects, concurrency control, real-time/as-of/historical balance reads, monthly statements, reconciliation with external payment rails, limits, fraud and dispute handling, plus sharding, replicas, recovery, and monitoring strategies for scale.

    System DesignOnline Assessment
  • CoinbaseMediumSoftware Engineer
    Design a task management system with TTL

    This question evaluates the ability to design in-memory data models and algorithms for time-based task assignment semantics, including TTL-based expiration, per-user quotas, priority-based listing, and correct handling of multiple concurrent assignments and completion rules.

    Software Engineering FundamentalsOnline Assessment
  • CoinbaseMediumSoftware Engineer
    Design an in-memory database with TTL and backups

    This question evaluates skills in designing and implementing in-memory data structures, TTL-based expiration, lexicographic prefix scans, and backup/restore snapshot semantics within the Coding & Algorithms domain.

    Coding & AlgorithmsOnline Assessment
  • CoinbaseMediumSoftware Engineer
    Design cloud storage system

    Design cloud storage system evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    System DesignOnline Assessment
  • CoinbaseHardSoftware Engineer
    Design scheduled payments and cancellation

    A Coinbase software-engineering take-home: design a scheduled payments service that creates, lists, updates, executes, and cancels future-dated one-time and recurring transfers with exactly-once ledger correctness. It tests distributed-systems architecture, idempotent REST/gRPC API design, data modeling, concurrency control, DST handling, retries/backoff, outage backfill, and observability. The model answer pins correctness on a single-writer state machine plus an idempotent ledger.

    System DesignOnline Assessment
  • CoinbaseHardMachine Learning Engineer
    Explain precision/recall and compute NN output

    This question tests the ability to calculate classification performance metrics, explain ensemble model dynamics, and perform manual forward propagation through a small neural network architecture.

    Machine LearningOnline AssessmentClassificationNeural NetworksEnsemble Methods
  • CoinbaseHardSoftware Engineer
    Implement a Coin-Constrained Jump Strategy

    Design a pathfinding algorithm to reach a target coordinate in the minimum number of jumps subject to physics-based velocity adjustments, obstacle avoidance, and a non-negative coin balance constraint.

    Coding & AlgorithmsOnline AssessmentBFSDynamic ProgrammingGraph Search
  • CoinbaseMediumSoftware Engineer
    Implement a versioned recipe management system

    This question evaluates data-structure design and state-management competencies, covering CRUD, case-insensitive search/sort semantics, user management, and versioning/rollback for an in-memory Recipe Management System in the Coding & Algorithms domain.

    Coding & AlgorithmsOnline Assessment
  • CoinbaseMediumSoftware Engineer
    Implement banking ops: transfer, top-k, cashback, merge

    This question evaluates a candidate's ability to design a robust in-memory banking system, covering transactional correctness, idempotency, concurrency control, delayed cashback scheduling, aggregate top-k queries, and data structure and complexity trade-offs within the Coding & Algorithms domain.

    Coding & AlgorithmsOnline Assessment
  • CoinbaseHardMachine Learning Engineer
    Implement local maxima, bagging, and k-means

    This problem tests array traversal for local maxima detection, statistical resampling techniques for bagging, and iterative convergence for k-means clustering.

    Coding & AlgorithmsOnline AssessmentAlgorithmsClusteringEnsemble Methods
  • CoinbaseMediumData Scientist
    Solve Aptitude Test: Logical, Numerical, Verbal Reasoning

    This question evaluates logical, numerical, and verbal reasoning along with rapid pattern recognition and time-limited decision-making relevant to pre-employment aptitude screens for data science roles.

    Coding & AlgorithmsOnline Assessment
  • ComposioMediumSoftware Engineer
    Generate a Semantic Dependency Graph from Tool Schemas

    Design an algorithm to construct an explainable dependency graph between API tools by matching output and input schemas and identifying unresolved requirements.

    Software Engineering FundamentalsOnline AssessmentGraph AlgorithmsData ProcessingSchema Matching
  • Concentric AiMediumSoftware Engineer
    Count Students Outside Their Height-Sorted Positions

    This problem tests your ability to compare a given array with its sorted version to identify indices where values do not match, assessing your proficiency in sorting and array indexing.

    Coding & AlgorithmsOnline AssessmentArraysSortingImplementation
  • Concentric AiMediumSoftware Engineer
    Maximize Profit Under a Bitwise-OR Limit

    Find a subset of items whose cumulative bitwise OR does not exceed a given limit such that the total profit is maximized.

    Coding & AlgorithmsOnline Assessmentbit-manipulationgreedyarrays
  • Concentric AiMediumSoftware Engineer
    Minimize Population-Weighted Manhattan Travel Cost

    This problem tests the ability to optimize a weighted distance metric by leveraging the independent nature of x and y coordinates in Manhattan geometry.

    Coding & AlgorithmsOnline AssessmentArraysSortingMath
  • ConfluentMediumSoftware Engineer
    Rank songs by pairwise user preferences

    This question evaluates the ability to aggregate pairwise user preferences, implement majority-based comparison rules with deterministic tie-breakers, and compute a global ranking via beat counts.

    Coding & AlgorithmsOnline Assessment
  • CrestaMediumSoftware Engineer
    Count the Leaves Left on a Grid After a Sequence of Wind Gusts

    Simulate wind gusts over a grid in which every cell holds a number of leaves: each gust shifts all leaves one cell in its direction, and leaves pushed off the edge are lost for good. Return how many leaves remain, testing careful two-dimensional state updates and boundary handling under time pressure.

    Coding & AlgorithmsOnline Assessment
  • CrestaMediumSoftware Engineer
    Longest Overlap Between the End of One String and the Start of Another

    Given two strings, return the length of the longest suffix of the first string that is also a prefix of the second. The problem tests precise string indexing, the direction of the overlap, and boundary cases such as no overlap at all or an overlap covering the whole shorter string.

    Coding & AlgorithmsOnline Assessment
  • CrestaMediumSoftware Engineer
    Recorded Walkthrough of a Past AI Project and Your Own Role in It

    A recorded behavioral item from a timed online assessment for a forward-deployed AI engineering role: walk through an AI project you built and explain exactly which parts you owned. It tests concise technical storytelling, clear ownership, evaluation and outcomes without a live interviewer to prompt you.

    Behavioral & LeadershipOnline Assessment
  • CrestaMediumSoftware Engineer
    Search a Directory Tree for a File and Return Its Absolute Path in Python

    Write a Python function that searches a directory and all of its subdirectories for a file matching a requirement and returns the file's absolute path. It tests practical use of os and pathlib, deterministic handling of multiple or missing matches, relative roots, symbolic links and unreadable directories.

    Software Engineering FundamentalsOnline Assessment
  • DRWEasyQuantitative Trader
    Analyze distribution of a 3-dice product

    This question tests the ability to analyze the probability distribution of the product of three independent discrete random variables and apply these statistical properties to practical risk management.

    Statistics & MathOnline AssessmentProbabilityExpectationStatistics
  • DRWMediumMachine Learning Engineer
    Build pipeline for imbalanced classification

    This interview question evaluates ML product requirements, data/labeling, modeling, serving architecture, evaluation, monitoring, and trade-offs in a realistic interview setting. A strong answer for Build pipeline for imbalanced classification states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    ML System DesignOnline Assessment
  • DRWEasyData Engineer
    Compute a Year-End Balance with Monthly Card Fees

    This problem tests logic implementation and data structure traversal, requiring the integration of conditional logic (fee waivers) into a sequential processing pipeline.

    Coding & AlgorithmsOnline AssessmentData ProcessingLogicAggregation
  • DRWEasyQuantitative Trader
    Compute expected arc length on a circle

    This question evaluates understanding of geometric probability, order statistics on a circle, and expectation computation for continuous random variables.

    Statistics & MathOnline Assessment