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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 6511–6540 of 9403 results
- OptiverMediumQuantitative ResearcherIntroduce yourself and justify quant research fit
This question evaluates communication, motivation, collaboration, and quantitative engineering competencies, including domain skills such as low-latency systems, data/ML for signal generation, simulation/backtesting, probabilistic/statistical literacy, and rapid estimation under pressure.
Behavioral & LeadershipTechnical Screen - OptiverMediumSoftware EngineerMaintain Price Levels For A Single-Symbol Order Book
Design and implement a single-symbol limit order book that tracks individual orders and aggregates quantity by price level, supporting order additions, modifications, cancellations, and best price queries.
Coding & AlgorithmsTechnical Screenhash-tableheapdesign - OptiverMediumData ScientistMake Two Apple Piles Equal With Doubling Moves
This question evaluates algorithmic problem-solving and discrete-mathematics competencies, focusing on reasoning about state transitions, invariants, and number-theoretic constraints within the Coding & Algorithms domain for data scientist roles.
Coding & AlgorithmsTechnical Screen - OptiverHardData ScientistMarket-Making Estimation Game: Optimal Confidence-Interval Strategy Over 5 Rounds
This question evaluates probabilistic reasoning, decision-theoretic optimization of confidence intervals, and sequential risk–reward trade-offs by requiring interval estimation under a nonstandard scoring rule, relevant to a Data Scientist and categorized in Machine Learning/statistical decision theory.
Machine LearningTechnical Screen - OptiverMediumData ScientistMatch alphanumeric patterns in a stream
This question evaluates skills in exact and approximate alphanumeric string matching, streaming pattern lookup, noise-tolerant comparison, and performance-oriented data structures and encodings.
Coding & AlgorithmsOnline Assessment - OptiverMediumData ScientistMinimize moves to transform floor layouts
This question evaluates algorithm design and combinatorial optimization skills, focusing on reasoning about minimal moves, greedy heuristics, and proving optimality within the Coding & Algorithms domain for data-science technical roles.
Coding & AlgorithmsOnline Assessment - OptiverHardQuantitative TraderOptimize interval-scoring strategy
This interview question evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer for Optimize interval-scoring strategy states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Statistics & MathTechnical Screen - OptiverMediumQuantitative TraderOptimize switching puzzle solution
This question evaluates the ability to model a Lights Out-style grid puzzle as a linear system over GF(2), linear algebra skills (Gaussian elimination and null-space reasoning), and combinatorial optimization for minimizing toggle moves.
Coding & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerOptiver Beat The Odds: Five Rapid-Fire Probability Brainteasers (Dice, Cards, Coins, Pigeonhole)
This collection of rapid-fire probability brainteasers evaluates probabilistic reasoning, combinatorics, symmetry-based thinking, conditional probability, and fast mental arithmetic to gauge quantitative intuition under time pressure.
Software Engineering FundamentalsOnline Assessment - OptiverMediumSoftware EngineerOptiver SWE Intern HR Screen: Project Deep Dive — Hardest Parts, What You'd Do Differently, and Questions to Ask
This Behavioral & Leadership interview prompt evaluates clarity of communication, ownership, reflective leadership, and the ability to concisely articulate one’s technical contributions during a short project deep-dive for a software engineering internship.
Behavioral & LeadershipHR Screen - OptiverMediumSoftware EngineerPlan for timed probability assessment
This question evaluates rapid probabilistic and statistical reasoning, time management and problem prioritization under strict timing, along with the ability to adapt approaches based on scoring rules and calculator restrictions, and it is classified in the Statistics & Math domain.
Statistics & MathOnline Assessment - OptiverMediumData ScientistProve a Tight Lower Bound on a Latin Square's Lower-Triangle Sum
This question evaluates combinatorial reasoning and discrete optimization skills—specifically understanding permutations in Latin squares, triangular-sum inequalities, and construction of extremal examples—within the Software Engineering Fundamentals domain for a Data Scientist position, and it primarily probes conceptual understanding with a constructive application component. Such problems are commonly asked to assess the ability to derive global bounds from local constraints and to exhibit matching constructions, signaling mathematical maturity and facility with combinatorial identities.
Software Engineering FundamentalsTechnical Screen - OptiverMediumQuantitative TraderQuant Trading Game: Expected-Value Betting and Market Making on Coins, Dice, and Cards
This question evaluates probabilistic reasoning, expected-value calculation, risk management, and market-making intuition under time pressure within a simulated trading game.
Machine LearningTechnical Screen - OptiverHardSoftware EngineerReviewing a Freight-Scheduler Codebase: Bugs, Data Structures, and Concurrency
This question evaluates a candidate's ability to perform code review and debugging on a large codebase, testing understanding of data structures, algorithmic complexity, deterministic allocation policies, capacity accounting, and concurrency correctness.
Software Engineering FundamentalsTechnical Screen - OptiverMediumSoftware EngineerSimulate return-weighted rebalancing strategy
Simulate return-weighted rebalancing strategy evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationTechnical Screen - OptiverMediumQuantitative TraderSolve a Skyscraper puzzle efficiently
This question evaluates understanding of constraint satisfaction and combinatorial search, testing competency in modeling Latin-square domains with visibility constraints, pruning and uniqueness verification, and algorithmic complexity analysis.
Coding & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerSolve numeric sequence pattern puzzles
This question evaluates pattern recognition and quantitative reasoning skills, requiring identification of numeric relationships, series properties, and simple number-theoretic or arithmetic transformations.
Statistics & MathOnline Assessment - OptiverHardData ScientistSolve probability and expectation problems
This problem tests your ability to calculate expected stopping times in a discrete random walk and your understanding of conditional expectation and symmetry in probability.
Statistics & MathOnline AssessmentProbabilityExpectationStochastic Processes - OptiverMediumSoftware EngineerSolve quick probability questions
This set evaluates core probability and combinatorics skills including discrete distributions, conditional probability, independence, expectation and variance, and basic stochastic processes such as gambler's ruin, situated in the Statistics & Math domain.
Statistics & MathOnline Assessment - OptiverMediumSoftware EngineerSolve three mini-game algorithm tasks
Solve three mini-game algorithm tasks evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - OptiverEasyQuantitative ResearcherStone Pile Doubling Game: Can One Pile Be Emptied?
This question evaluates a candidate's algorithmic reasoning and discrete-mathematics skills, particularly understanding deterministic state transitions, invariants, and cycle detection in iterative processes.
Coding & AlgorithmsTechnical Screen - OptiverMediumSoftware EngineerThread-Safe Stock Inventory: Buy and Sell Without Overselling
This question evaluates understanding of concurrent programming, synchronization primitives, atomicity, and correctness of shared mutable state by requiring implementation of a thread-safe inventory that prevents overselling and preserves updates.
Coding & AlgorithmsTechnical Screen - OptiverEasyQuantitative ResearcherTrading Game: Expected-Value Betting, Kelly Sizing, and Arbitrage Under Time Pressure
This question evaluates quantitative probability reasoning, expected-value computation, risk-sizing (including Kelly-style sizing), arbitrage recognition, and market-making intuition within a live trading simulation.
Machine LearningTechnical Screen - OptiverMediumSoftware EngineerValidate a Binary Tree Built from Directed Edges
This question evaluates understanding of tree and graph fundamentals including parent-child constraints, duplicate-edge detection, cycle detection, node-degree limits, and in-order traversal semantics.
Coding & AlgorithmsOnline Assessment - OracleMediumBackend EngineerAdd One to an Integer Stored as Digits Without ArrayList
This problem tests array manipulation skills and the ability to handle carry-over logic in fixed-size numerical representations.
Coding & AlgorithmsOnsiteArraysMathAlgorithms - OracleEasySoftware EngineerAlign Multiple Teams Around a Shared Technical Outcome
This question assesses your ability to navigate cross-functional technical dependencies, manage conflicting team priorities, and drive alignment toward a shared objective without formal authority.
Behavioral & LeadershipOnsiteLeadershipCross-functionalConflict-Resolution - OracleMediumSoftware EngineerAnswer Behavioral Leadership Questions
This question assesses a candidate's ability to demonstrate leadership through ownership, conflict resolution, and the ability to influence technical direction in a high-pressure environment.
Behavioral & LeadershipOnsiteLeadershipOwnershipCommunication - OracleMediumSoftware EngineerApply operations efficiently using Command pattern
This problem tests the application of the Command design pattern to encapsulate, track, and optimize a series of state mutations on a shared object.
Software Engineering FundamentalsOnsiteDesign PatternsOOPCommand Pattern - OracleMediumSoftware EngineerApproximate a Square Root Across Values Above and Below One
This problem tests binary search on a continuous search space and the ability to handle numerical precision for numbers both greater than and less than one.
Coding & AlgorithmsTechnical ScreenBinary SearchMathNumerical Methods - OracleMediumSoftware EngineerBehavioral: simplifying a complicated product or system and proving it worked
A behavioral question asking for a complicated product or system the candidate made simpler. It evaluates how they diagnosed the source of the complexity, decided what to remove or hide, brought users and stakeholders along, and measured whether the simplification actually helped.
Behavioral & LeadershipOther
Optiver
Oracle