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Software Engineer 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 1921–1950 of 2810 results
- OptiverMediumSoftware EngineerDesign a circular queue data structure
This problem tests your ability to implement a fixed-capacity circular queue using a static array, focusing on efficient pointer arithmetic and state management.
Coding & AlgorithmsTechnical ScreenData StructuresArraysQueues - OptiverMediumSoftware EngineerDesign a queue and analyze tradeoffs
This question evaluates understanding of FIFO data structures, algorithmic complexity analysis, memory and cache behavior, and concurrent access concerns.
Coding & AlgorithmsTechnical Screen - OptiverHardSoftware EngineerDesign a subscription push service
Design a subscription push service 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 DesignTechnical Screen - OptiverMediumSoftware EngineerDesign an object-oriented queue and compare implementations
Design an object-oriented queue and compare implementations evaluates engineering fundamentals, trade-offs, examples, pitfalls, and operational implications in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Software Engineering FundamentalsTechnical Screen - OptiverHardSoftware EngineerDesign and backtest a trading strategy
This question evaluates a candidate's ability to design and rigorously evaluate a minute-level mean-reversion trading strategy, encompassing quantitative finance competencies such as signal construction, risk controls, position sizing, transaction-cost modeling, reproducible backtesting, and statistical validation; it belongs to the Analytics & Experimentation category within financial time-series and backtesting. It is commonly asked because it tests both practical implementation skills (reproducible backtests and walk-forward validation) and conceptual understanding (overfitting, data-snooping, and statistical significance testing), requiring a mix of practical application and conceptual statistical reasoning.
Analytics & ExperimentationTechnical Screen - OptiverHardSoftware EngineerDetect Currency Arbitrage After a Cycle Fee
You are given a matrix of positive currency exchange rates, where rates[i][j] units of currency j are received for one unit of currency i. Work through the function contract, boundary cases, correctness argument, and time and space complexity expected in a production-quality solution.
Coding & AlgorithmsTechnical Screen - OptiverMediumSoftware EngineerDetect currency arbitrage with costs
This question evaluates a candidate's competency in algorithmic problem modeling, graph-based cycle detection, and numerical reasoning about exchange rates and transaction costs.
Coding & AlgorithmsTechnical Screen - OptiverHardSoftware EngineerFind the Color Probability After Discarding Cards
This problem tests your understanding of conditional probability, combinatorics, and how dependent events (sampling without replacement) impact statistical expectations.
Statistics & MathTechnical ScreenProbabilityCombinatoricsStatistics - OptiverHardSoftware EngineerFind the Probability That the Three Smallest Dice Sum to Three
This problem tests combinatorics and probability theory by requiring the derivation of the exact probability that the three smallest values of four independent dice rolls sum to exactly three.
Statistics & MathTechnical ScreenProbabilityCombinatoricsStatistics - 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 - 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 - 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 - 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 - 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 EngineerCheck That a String of Three Bracket Types Is Properly Nested
Decide whether a string made of round, square and curly brackets is properly nested, meaning every closing bracket matches the most recently opened bracket of the same type and nothing is left open. Tests careful handling of nesting order, crossing pairs and unmatched brackets at either end.
Coding & AlgorithmsTechnical Screen - OracleMediumSoftware EngineerClassify Tree Nodes in SQL
Tests the ability to write conditional logic and subqueries/joins in SQL to classify hierarchical tree nodes into 'Root', 'Inner', or 'Leaf'.
Data Manipulation (SQL/Python)Technical ScreenSQLPostgreSQLTrees - OracleMediumSoftware EngineerCount anagram-based replacements per phrase
This question evaluates skills in string processing, anagram grouping, frequency mapping, and combinatorial counting to determine how many phrase variations arise from permissible replacements in the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - OracleMediumSoftware EngineerDecide Whether a Parenthesis String With Star Wildcards Can Be Balanced
Decide whether a string of parentheses and stars can become a balanced parenthesis string when each star may independently act as an opening parenthesis, a closing parenthesis or an empty string. Tests reasoning over many possible replacements at once and edge cases with unmatched parentheses near either end.
Coding & AlgorithmsTechnical Screen - OracleMediumSoftware EngineerDesign a Video Upload Service for 100 GB Files with Chunked, Resumable Uploads
A system design question about building a service that accepts video uploads of up to 100 GB. It covers moving very large files efficiently, splitting them into chunks, resuming interrupted uploads, choosing storage for bytes and metadata, and scaling to many concurrent uploads.
System DesignTechnical Screen - OracleEasySoftware EngineerDesign structure for first unique login user
This question evaluates a candidate's ability to design an efficient online data structure that maintains a stream of login events and supports constant-time updates and queries for the earliest user with exactly one login.
Coding & AlgorithmsTechnical Screen - OracleHardSoftware EngineerEvaluate Subjective and Nondeterministic Agent Outputs
Create an evaluation program for subjective, nondeterministic AI-agent outputs when direct user feedback is sparse. Cover stratified tasks, versioned rubrics, repeated sampling, calibrated human review, judge agreement and bias, uncertainty-aware comparisons, severe-failure gates, online signals, and rollback criteria.
ML System DesignTechnical Screen - OracleMediumSoftware EngineerExplain What Motivates You at Work
This question assesses your self-awareness, professional values, and how your personal work style aligns with the challenges of a fast-paced software engineering environment.
Behavioral & LeadershipTechnical ScreenBehavioralSelf-AwarenessSoft Skills - OracleHardSoftware EngineerHow do you prioritize and handle failures?
This question evaluates prioritization, incident-response and failure-management competencies including stakeholder communication, customer-impact mitigation, and learning-from-failure within the Behavioral & Leadership category for software engineers, emphasizing practical, experience-based application rather than abstract theory.
Behavioral & LeadershipTechnical Screen - OracleHardSoftware EngineerImplement Queue Operations Using Two Stacks
Implement queue enqueue, dequeue, and peek operations using exactly two LIFO stacks. The challenge tests transfer invariants, output ordering, amortized O(1) reasoning, large operation sequences, empty input, and compliance with restrictions against queue-like shortcuts.
Coding & AlgorithmsTechnical Screen - OracleEasySoftware EngineerImplement a Paginated Medical-Record Filter Without Guessing an Ambiguous Rule
This problem tests your ability to handle ambiguous business logic through requirement clarification and implement a robust, paginated filtering system for sensitive data.
Software Engineering FundamentalsTechnical ScreenPaginationRequirementsData-Validation - OracleHardSoftware EngineerImplement in-memory data structures and booking API
This problem tests your ability to design a thread-safe, in-memory booking system using efficient data structures to handle temporal queries and capacity management.
Coding & AlgorithmsTechnical ScreenHash MapConcurrencyAPI Design - OracleMediumSoftware EngineerMaximum of Fixed-Window Minimums
Tests the ability to compute sliding-window minima in linear time using a monotonic deque and determine the maximum value among those minima.
Coding & AlgorithmsTechnical Screensliding-windowmonotonic-queuedeque - OracleMediumSoftware EngineerMove Forward When Requirements Are Ambiguous
This question assesses a candidate's ability to navigate project uncertainty by balancing proactive problem-solving with effective stakeholder communication.
Behavioral & LeadershipTechnical ScreenBehavioralCommunicationProject Management - OracleMediumSoftware EngineerRearrange an Integer Array into Its Next Lexicographic Arrangement
A coding problem that asks you to rearrange an integer array into the next lexicographically greater arrangement of its values, wrapping around to ascending order when the array is already the largest. It tests reasoning about lexicographic order, repeated values and complexity analysis.
Coding & AlgorithmsTechnical Screen
Optiver
Oracle