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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.
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- 546
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- 11
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Showing 481–510 of 781 results
- OptiverMediumSoftware EngineerCalculate Days Between Arbitrary Gregorian Dates
This problem tests the ability to implement a calendar-based calculation algorithm, specifically handling leap year logic and modular arithmetic without iterating through every day.
Coding & AlgorithmsOnline AssessmentAlgorithmsMathCalendar - OptiverMediumQuantitative TraderCompare two programs for equivalence
This question evaluates program-equivalence reasoning skills, including understanding of language semantics (mutation, ordering stability, integer overflow/underflow, integer-division behavior), competency in comparing time and space complexity, and the ability to design property-based tests and edge cases.
Coding & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerCompute negative-price probability after n steps
This question evaluates understanding of discrete probability distributions and random-walk processes within Statistics & Math, testing skills in binomial modeling and numeric computation for probabilistic outcomes.
Statistics & MathOnline Assessment - OptiverMediumQuantitative TraderCompute odds under time pressure
This question evaluates probabilistic reasoning and combinatorial calculation skills, including conditional probability, distributional thinking and the ability to convert probabilities into odds.
Statistics & MathOnline Assessment - OptiverEasySoftware EngineerCompute permutations with repeated letters
This question evaluates combinatorics and counting principles within the Statistics & Math domain, focusing on permutations with repeated characters and the generalization to multiple symbol counts.
Statistics & MathOnline Assessment - OptiverEasyData ScientistCompute probabilities and expectations in random processes
This question evaluates proficiency in probability theory, combinatorics, and mathematical expectation through a series of rapid-fire brain-teasers. It tests the ability to set up clean probabilistic models, apply the right technique, and derive exact closed-form answers under time pressure — skills commonly assessed in quantitative and data science interviews.
Statistics & MathOnline Assessment - OptiverMediumSoftware EngineerCount the Days Between Two Dates
This question evaluates date arithmetic, calendar logic, string parsing, and correct leap-year handling as implementation competencies. It is commonly asked to assess algorithmic correctness and edge-case handling across month, year, and leap boundaries, falls under the Coding & Algorithms domain (date/calendar problems), and targets practical application rather than purely conceptual understanding.
Coding & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerCourier Drone: Fastest Fixed-Distance Segment From Tick Logs
From per-tick distance logs, find the highest average speed over any time span that covers exactly a target distance, where spans may start and end partway through a tick. Tests prefix sums, linear interpolation, and showing that an optimal span touches a tick boundary.
Coding & AlgorithmsOnline Assessmentprefix-sumsbinary-searchsliding-window - OptiverMediumSoftware EngineerDays Between Two Calendar Dates
This question evaluates proficiency in date and calendar arithmetic, specifically handling varying month lengths, leap year rules, and computing absolute differences between dates.
Coding & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerDesign a Balloon Festival Simulator
This question evaluates proficiency in data structures, event-driven simulation, numerical aggregation of spatially varying fields, and time-based state tracking for mutable entities.
Coding & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerDesign a Multi-Level Expiring Item Store
Design an in-memory multi-level key-value store where items are stored at specific priority levels with individual expiration timestamps, supporting query fallback and expiration cleanup.
Software Engineering FundamentalsOnline AssessmentData StructuresDesignHash Table - OptiverHardSoftware EngineerDesign a News Subscription Processing Engine
Design and implement an in-memory news subscription processing engine that supports attribute-based filtering, deduplication, unsubscription, and unacknowledged delivery tracking.
Software Engineering FundamentalsOnline AssessmentLow-Level DesignPub-SubConcurrency - OptiverMediumSoftware EngineerDesign a balloon stability tracker
This question evaluates event-driven simulation, time-ordered state management, floating-point numerical evaluation of aggregate functions, and data-structure design for tracking dynamic object states and stability thresholds; it falls under the Coding & Algorithms domain, specifically simulation, event processing, and algorithmic data structures.
Coding & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerDesign a satellite propagation simulator
Optiver software-engineer take-home: implement a SatelliteNetwork that simulates timed message propagation over an undirected graph and fires OnSatelliteReportedBack callbacks in deterministic order. It tests graph modeling, discrete-event simulation, priority-queue scheduling, and careful handling of 10s-per-hop forwarding and 30s report timing with tie-breaking by SatelliteId.
Coding & AlgorithmsOnline Assessment - OptiverHardSoftware EngineerDesign a topic-based news subscription system
This question evaluates system design skills for building a topic-based news subscription service, focusing on streaming ingestion, relevance filtering, sliding-window rate limiting, de-duplication, ordered delivery, and data structure choices for in-memory operation.
System DesignOnline Assessment - OptiverMediumQuantitative TraderDevise sequence-rule detection strategy
This question evaluates pattern-recognition, algorithm design, statistical reasoning, and model-selection skills required for sequence inference and candidate-term prediction in the Coding & Algorithms / Data Science domain.
Coding & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerEstimate expected comparisons in a BST
Estimate expected comparisons in a BST 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 & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerFastest 1000 Meters: Max Average Speed from 5-Second Distance Splits
Given the meters a runner covers in each consecutive 5-second interval, find the highest average speed over any continuous stretch of exactly 1000 meters, where stretches may start or end mid-interval. Tests sliding-window reasoning, linear interpolation at boundaries and edge cases such as one interval exceeding 1000 meters.
Coding & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerFastest 500-Unit Stretch on a Conveyor Belt From Tick Logs
Given how many units of material a conveyor belt moves during each fixed-length tick, find the maximum average speed over any continuous time stretch covering exactly 500 units, where the stretch may start or end mid-tick.
Coding & AlgorithmsOnline Assessmentsliding-windowtwo-pointersinterpolation - OptiverMediumSoftware EngineerFastest Rolling One-Kilometer Average Speed from 5-Second Distance Samples
Given the meters a runner covers in each 5-second interval, find the fastest average speed over a rolling one-kilometer stretch, defined as the shortest run of intervals ending at each point that covers at least 1000 meters. It tests sliding-window reasoning over large arrays and precise window definitions.
Coding & AlgorithmsOnline Assessment - OptiverHardData ScientistFind missing numbers in sequences
This problem tests pattern recognition and algorithm design for identifying missing terms in a sequence that may follow arithmetic, geometric, polynomial, or linear recurrence rules.
Coding & AlgorithmsOnline AssessmentAlgorithmsPattern RecognitionNumerical Analysis - OptiverHardData ScientistFind next terms in sequences
This question evaluates pattern recognition, numerical reasoning, and sequence-inference competency across arithmetic, fractional, and recurrence-style relationships, and falls under the Statistics & Math domain relevant for data scientist roles.
Statistics & MathOnline Assessment - OptiverHardData ScientistHow to rank statements by likelihood
This problem tests your ability to translate statistical distributions and categorical data into ranked probabilistic likelihoods, accounting for uncertainty and sample size variance.
Machine LearningOnline AssessmentProbabilityStatisticsBayesian Inference - OptiverMediumSoftware EngineerIdentify OS component causing process starvation
This question evaluates understanding of process scheduling, kernel-level resource allocation, and starvation-related concurrency issues within the operating systems domain.
Coding & AlgorithmsOnline Assessment - OptiverHardSoftware EngineerImplement a Multicore Overheat Prevention Controller
Simulate a multicore thermal controller with delayed workload changes, shared passive cooling, vibration-sensitive active cooling, shutdown and restart thresholds, and transition-only tick output.
Coding & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerImplement price-based order matcher
This question evaluates competency in data structures and algorithmic design for price-based order matching systems, including priority-based matching, efficient order book maintenance, and deterministic tie-breaking requirements.
Coding & AlgorithmsOnline Assessment - 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 - 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
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