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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.
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Showing 1381–1410 of 2810 results
- LinkedInMediumSoftware EngineerRandomized String Multiset With Average O(1) Insert, Remove and Weighted Random Pick
Design a collection of strings that allows duplicates and supports insert, remove and a random pick in average constant time, where each stored occurrence is equally likely to be returned. It tests hash map and array layout, index bookkeeping on removal, and how string keys change the cost analysis.
Software Engineering FundamentalsTechnical Screen - LinkedInHardSoftware EngineerReduce Stale Listings in a Job Marketplace
Design an auditable staleness-detection and remediation engine for a global job marketplace that aggregates heterogeneous signals, enforces graduated interventions, and supports low-latency employer appeals.
System DesignTechnical ScreenDistributed SystemsEvent-Driven ArchitectureAudit Logging - LinkedInEasySoftware EngineerReview a Web Application Architecture
This question evaluates system design competencies such as scalability, reliability, fault tolerance, database architecture, load balancing, external dependency management, and observability, and is categorized under System Design.
System DesignTechnical Screen - LinkedInMediumSoftware EngineerSecond-Smallest Value in a Min Tournament Tree in Logarithmic Time
Given a full binary tournament tree stored in array order, where each internal node holds the smaller of its two children, return the second-smallest leaf value in logarithmic time. It tests reasoning about how a knockout structure constrains where the runner-up can be, array-based tree indexing, and justifying a partial search.
Coding & AlgorithmsTechnical Screen - LinkedInHardSoftware EngineerShortest Word Distance Queries
Tests designing an inverted index and using two-pointer or binary search techniques to efficiently compute the minimum absolute index distance between word occurrences across repeated queries.
Coding & AlgorithmsTechnical Screenhash-tabletwo-pointersbinary-search - LinkedInMediumSoftware EngineerSolve common string and subarray problems
Assesses core string and array manipulation skills by requiring string reversal and contiguous-subarray computations for maximum sum and maximum product, identified under the Coding & Algorithms category.
Coding & AlgorithmsTechnical Screen - Listen LabsMediumSoftware EngineerParse a Truncated Streaming JSON Prefix of Strings and Nested Arrays
Write a function that turns a truncated prefix of streamed JSON, made only of strings and nested arrays, into the value received so far. It tests careful parsing of half-received strings, unclosed arrays and input that ends after a comma, along with writing your own edge-case tests.
Coding & AlgorithmsTechnical Screen - Listen LabsMediumSoftware EngineerReconstruct a Warehouse Pick-List From a Dropped Scanner Feed
Write a function that turns a scanner feed cut off mid-transmission into the best pick-list it can represent so far, recovering half-written labels and unfinished bin groupings. Tests careful state-machine parsing of truncated nested data.
Coding & AlgorithmsTechnical Screenparsingstacksstrings - Lowe'sMediumSoftware EngineerExplain Python internals and practices
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Explain Python internals and practices states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - Lowe'sHardSoftware EngineerExplain cloud computing fundamentals
This interview question evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer for Explain cloud computing fundamentals states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignTechnical Screen - Lowe'sMediumSoftware EngineerFind longest unique substring
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Find longest unique substring states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - Luma AIHardSoftware EngineerImplement Refactoring Assessment Features
This problem tests your ability to manage stateful data with temporal versioning and reconstruct valid paths in a graph while ensuring data integrity under constraints.
Coding & AlgorithmsTechnical ScreenGraphsData StructuresVersioning - Luma AIHardSoftware EngineerManage Prompt and Model Behavior in Production
This question tests the ability to design an end-to-end configuration management and observability system for LLM applications that ensures reproducibility, safety, and rapid recovery from performance drift.
ML System DesignTechnical ScreenLLMOpsSystem DesignObservability - LyftMediumSoftware EngineerSmallest Covering Window in a String
Tests using the two-pointer sliding window pattern combined with frequency counting to find the shortest substring satisfying multiset inclusion constraints in linear time.
Coding & AlgorithmsTechnical Screensliding-windowtwo-pointershash-table - MathWorksMediumSoftware EngineerDetermine Whether P's Position Is Unique
This question evaluates constraint-satisfaction and combinatorial search skills, specifically reasoning about spatial relations and whether a target's location is uniquely determined among all valid assignments on a discrete grid.
Coding & AlgorithmsTechnical Screen - MathWorksMediumSoftware EngineerExplain why EDG and why you fit
This question evaluates motivation, cultural alignment, communication skills, and the ability to present concrete, impact-driven examples from prior work, and it falls under the Behavioral & Leadership domain.
Behavioral & LeadershipTechnical Screen - MathWorksEasySoftware EngineerHow to maximize rewards with exactly k tasks
This Coding & Algorithms question evaluates a candidate's ability to perform combinatorial optimization and benefit-based assignment reasoning on arrays, testing algorithm design, complexity-aware implementation, and quantitative decision-making in constrained assignment problems.
Coding & AlgorithmsTechnical Screen - MathWorksEasySoftware EngineerMaximize minimum after K decrements
This Coding & Algorithms question evaluates algorithmic problem-solving skills in array manipulation and constrained optimization, testing competency in reasoning about value distribution, large numeric bounds, and performance under tight complexity limits.
Coding & AlgorithmsTechnical Screen - MathWorksEasySoftware EngineerMinimize shortest path by adding weight-1 edges
This question evaluates proficiency in graph algorithms, shortest-path computation, and algorithmic optimization when augmenting a directed weighted graph with additional unit-weight edges.
Coding & AlgorithmsTechnical Screen - MercorMediumSoftware EngineerBehavioral: The Project You Are Leading and Why You Are Its Owner
Describe the project you are currently leading, then defend why you are its owner rather than just a participant. The behavioral question tests whether you can explain a project crisply and back up a claim of ownership with specific decisions, risks you handled, accountability for setbacks and honest boundaries.
Behavioral & LeadershipTechnical Screen - MercorMediumSoftware EngineerCharge-Then-Save: Making a Checkout Handler Safe Under Retries
Review a ticket-checkout handler that bills a card through a remote gateway and then saves an order row, explain every way it breaks when calls fail or are retried, and redesign it. Tests reasoning about partial failure, idempotency, and reconciliation.
Software Engineering FundamentalsTechnical Screenidempotencydistributed-systemspayments - MercorMediumSoftware EngineerCheck-and-Insert for a Million User IDs: Balancing Latency, Memory and Accuracy
Design a check-and-insert service for about a million user IDs that reports whether an ID already exists and adds it if not. It tests memory estimates, data structure choice, atomic inserts under concurrency, trading memory for accuracy with compact filters, and durable on-disk storage with fast reads and writes.
System DesignTechnical Screen - MercorMediumSoftware EngineerCode Review: A Ride Fare Method That Charges a Card Then Logs the Trip
Review a Java method that charges a rider's card through an external processor and then writes a trip record, and explain what goes wrong if the caller fails mid-call and how to fix it.
Software Engineering FundamentalsTechnical Screencode-reviewidempotencydistributed-systems - MercorEasySoftware EngineerCode Review: Find the Problems in a Python Dict-Based Memoization Cache
A Python code review question about a function that memoizes an expensive computation in a module-level dictionary. It tests whether a candidate can find correctness, memory, concurrency and key-equality problems in simple caching code and propose fixes with clear trade-offs.
Software Engineering FundamentalsTechnical Screen - MercorMediumSoftware EngineerCode Review: Improve a Java Method That Builds a CSV String
A Java code-reading question: review a short method that concatenates a list of rows into a CSV string and propose improvements. It tests knowledge of string-building performance, separator and escaping rules for CSV, null handling, streaming output for large exports, and risks when files are opened in spreadsheets.
Software Engineering FundamentalsTechnical Screen - MercorMediumSoftware EngineerCode Review: Partial Failure in a Java Payment Method That Charges Then Records
A Java code-reading question about a payment method that charges an external provider and then inserts a database record, focused on what happens when the client fails in the middle of the call. It tests reasoning about partial failures, retries, idempotency keys, payment states, and reconciliation with the provider.
Software Engineering FundamentalsTechnical Screen - MercorMediumSoftware EngineerCode Review: Thread Safety of a Python Compute-and-Cache Function
Review a Python function that checks a dictionary cache, runs an expensive computation on a miss, and stores the result, assuming concurrent callers. It probes thread safety under simultaneous misses, making the computation run once per input, where to place a lock without serializing cache hits, and how Python dictionaries behave under concurrent reads and writes.
Software Engineering FundamentalsTechnical Screen - MercorHardSoftware EngineerCompare Merge Sort with Factorial and Randomized Inefficient Sorts
Tests deep understanding of sorting algorithms, contrasting optimal divide-and-conquer strategies (Merge Sort and its adaptive variants) against factorial and randomized paradigms (Permutation Sort and Bogo Sort) across worst-case and expected complexity bounds.
Software Engineering FundamentalsTechnical ScreenDivide and ConquerSortingComplexity Analysis - MercorMediumSoftware EngineerCompare processes and threads in Linux and Python
This question evaluates understanding of operating-system level concurrency versus language-level concurrency, specifically distinctions between processes and threads on Linux, the Global Interpreter Lock in Python, and trade-offs between Python threading and multiprocessing for performance.
Software Engineering FundamentalsTechnical Screen - MercorMediumSoftware EngineerDebug a Java CSV Export Function for Output and Performance Bugs
A debugging exercise on a small Java function that converts rows of string fields into CSV text for import by another system. You find what is wrong with its output and why it slows down sharply on large exports, then fix it. It tests string handling, the cost of building strings in loops, and edge-case tests.
Software Engineering FundamentalsTechnical Screen
LinkedIn
Luma AI
Lyft
MathWorks
Mercor