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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 2251–2280 of 2336 results

  • VisaMediumSoftware Engineer
    Maintain pair-sum counts under replacements

    This question evaluates the ability to design dynamic data structures and perform algorithmic complexity analysis for maintaining pair-sum counts under element replacements, testing skills in efficient query/update handling and scalability.

    Coding & AlgorithmsOnsite
  • VoleonHardSoftware Engineer
    Implement Kac ring with O(1) color and kstep

    This question evaluates understanding of algorithmic state representation, modular arithmetic, and efficient update/query design by requiring a Kac ring implementation that supports constant-time k-step advancement and O(1) aggregate color reporting.

    Coding & AlgorithmsOnsite
  • VoleonHardSoftware Engineer
    Process exchange prints, volume checks, and client orders

    This problem tests your ability to manage high-frequency time-series data using sliding windows and stateful order tracking to enforce trading constraints.

    Coding & AlgorithmsOnsiteSliding WindowStream ProcessingTime-Series
  • Walmart LabsMediumSoftware Engineer
    Design a Read- and Write-Heavy Product Catalog Service

    Design a scalable, highly available product catalog platform supporting both high-frequency merchant updates and massive shopper read traffic while maintaining data integrity and search consistency.

    System DesignOnsitesystem-designcqrscaching
  • Walmart LabsEasySoftware Engineer
    Design aggregator for multiple downstream services

    This question assesses the ability to design an API Gateway or Aggregator service that coordinates requests to multiple downstream microservices while managing latency, partial failures, and data aggregation.

    System DesignOnsiteMicroservicesConcurrencyFault Tolerance
  • Walmart LabsHardSoftware Engineer
    Design an E-Commerce Checkout Flow That Prevents Concurrency Bugs

    Design the checkout flow for a large online retailer, from cart to a confirmed, paid order, with the emphasis on preventing concurrency bugs. It tests stock reservation without overselling, idempotent order placement and payment, handling of carts and prices that change mid-checkout, and recovery from partial failures.

    System DesignOnsite
  • Walmart LabsHardSoftware Engineer
    Design and Implement an In-Memory Job Scheduler for Delayed Jobs

    Design and implement an in-memory job scheduler that runs submitted jobs after a delay and supports cancellation and shutdown. It tests choosing a structure ordered by due time, thread-safe coordination without busy waiting, worker concurrency, failure isolation and the trade-offs of recurring or persistent jobs.

    Software Engineering FundamentalsOnsite
  • Walmart LabsHardSoftware Engineer
    Find the Single Repeated Value Among n + 1 Integers Drawn from 1 to n

    Given an array of n + 1 integers whose values all lie between 1 and n, return the one value that repeats, possibly several times. The challenge is solving it without modifying the array and with constant extra memory, which rules out sorting, hash sets and counting arrays.

    Coding & AlgorithmsOnsite
  • Walmart LabsEasySoftware Engineer
    Handle conflict and motivate engineering teams

    This question evaluates leadership competencies including conflict resolution, stakeholder management, and team motivation, emphasizing interpersonal decision-making and balancing technical quality with timelines.

    Behavioral & LeadershipOnsite
  • Walmart LabsHardSoftware Engineer
    Product of All Other Elements for Each Index Without Division

    For each position of an integer array, compute the product of all the other elements in linear time and without using division. It tests careful handling of zeros, negative values and repeated values, and planning a single efficient pass when the obvious division shortcut is not allowed.

    Coding & AlgorithmsOnsite
  • WayfairMediumSoftware Engineer
    Design the Domain Model for an Automated Parking Garage

    This problem tests object-oriented design skills by requiring the modeling of physical interactions (vehicles, spots, sensors) and transactional state management in an automated parking system.

    Software Engineering FundamentalsOnsiteObject-Oriented DesignConcurrencyState Machine
  • WaymoMediumSoftware Engineer
    2D Max Pooling That Also Returns the Coordinates of Each Window Maximum

    Implement 2D max pooling with a k-by-k window and a stride, and for each window also return the row and column of its maximum, breaking ties by smallest row then column. Tests window indexing without padding, output sizing, and argmax bookkeeping.

    Coding & AlgorithmsOnsite
  • WaymoMediumSoftware Engineer
    Can You Reach the Last Index?

    This problem tests your ability to determine reachability in a sequence using greedy strategy or dynamic programming to optimize pathfinding.

    Coding & AlgorithmsOnsiteArraysGreedyDynamic Programming
  • WaymoMediumSoftware Engineer
    Character at a Position in a Run-Length Encoded String Without Decoding

    Given a run-length encoded string such as B1A2E3C1, return the character at each queried position of the decoded sequence without decoding it. Runs can be very long, so the task tests prefix sums over run lengths and fast lookup per query.

    Coding & AlgorithmsOnsite
  • WaymoMediumSoftware Engineer
    Count Squares Formed by Intersections of Vertical and Horizontal Segments

    Given vertical and horizontal line segments defined by start and end points, count the axis-aligned squares whose four corners are all segment intersection points. Tests intersection detection, square enumeration, and faster ways to find which segments cross each other.

    Coding & AlgorithmsOnsite
  • WaymoMediumSoftware Engineer
    Deduplicate a 256 GB File on a Machine With 128 MB of Memory

    Remove duplicate records from a single 256 GB file on a machine with only 128 MB of memory. Tests external-memory techniques such as hash partitioning and external merge sort, skew handling, I/O cost, open-file limits, and preserving the original order.

    Software Engineering FundamentalsOnsite
  • WaymoMediumSoftware Engineer
    Describe a Complex Project You Worked On and Why It Was Challenging

    Behavioral hiring-manager question: describe a complex project you worked on and explain why it was challenging, often after a resume walk-through. Tests choosing a project that fits the level, naming the real difficulty, personal ownership and outcomes.

    Behavioral & LeadershipOnsite
  • WaymoMediumSoftware Engineer
    Describe a Project You Are Proud Of

    This question tests your ability to articulate a technical contribution, demonstrate engineering judgment, and communicate impact within a high-stakes team environment.

    Behavioral & LeadershipOnsiteBehavioralCommunicationOwnership
  • WaymoMediumSoftware Engineer
    Design Reliable Command Delivery Between Autonomous Vehicles and the Cloud

    Design a resilient, secure command dispatch and execution system between a cloud fleet management platform and autonomous vehicles operating over unreliable cellular networks.

    System DesignOnsiteDistributed SystemsIoTNetworking
  • WaymoHardSoftware Engineer
    Design a Fleet That Collects Mapping Data

    Design fleet mapping-data collection with coverage goals, task assignment, offline buffering, resumable uploads, provenance, quality validation, and re-collection workflows.

    System DesignOnsite
  • WaymoMediumSoftware Engineer
    Design a Hybrid Evaluation Platform

    This problem tests your ability to design a multi-modal evaluation infrastructure that balances automated LLM-based grading with human-in-the-loop (HITL) verification to ensure high-fidelity ML model performance metrics.

    ML System DesignOnsiteMLOpsData InfrastructureHuman-in-the-loop
  • WaymoMediumSoftware Engineer
    Design a Matchmaking Service With Join, Cancel, Matching, Notification and Expiry

    Design a matchmaking service that lets players join and cancel requests, pairs compatible players, notifies both, and handles disconnects and expired requests. Tests request state machines, atomic matching, partitioned waiting pools and reliable notification.

    System DesignOnsite
  • WaymoMediumSoftware Engineer
    Design a Ride Scheduler

    This problem tests your ability to design a robust scheduling system that handles dynamic task insertion, state transitions, and time-based prioritization using object-oriented principles.

    Software Engineering FundamentalsOnsiteSystem DesignObject-Oriented DesignPriority Queue
  • WaymoMediumSoftware Engineer
    Design a Shared-Ride Matching and Trip Service

    This problem tests the ability to architect a low-latency geospatial matching system that handles concurrency, real-time vehicle tracking, and the complex state management required for shared-ride optimization.

    System DesignOnsiteGeospatialConcurrencyScalability
  • WaymoMediumSoftware Engineer
    Design an Object Storage Service With Buckets, Keys and Durable Blob Storage

    Design an object storage service where clients store, read, list and delete blobs by key inside buckets. Covers the API, separating metadata from data nodes, replication versus erasure coding, visibility on write, prefix listing, repair and garbage collection.

    System DesignOnsite
  • WaymoMediumSoftware Engineer
    Design an Online Experiment

    This question tests the ability to design a statistically sound A/B test for a machine learning model update in a real-world, dynamic environment, focusing on metric selection and mitigation of interference.

    Machine LearningOnsiteExperimentationA/B TestingCausal Inference
  • WaymoMediumSoftware Engineer
    Does a Seven-Segment LED Digit Display Read the Same Rotated 180 Degrees?

    Decide whether a row of digits on a seven-segment LED display reads the same after the whole display is rotated by 180 degrees. Tests modeling each digit as lit segments, mapping segments under rotation, and comparing the reversed display.

    Coding & AlgorithmsOnsite
  • WaymoMediumSoftware Engineer
    Drive a Car to an Unseen Destination Using Only Local Directions Without Circling

    A car must reach an unseen destination while only learning which directions are open at each step. Implement the search that finds it without driving in circles, testing depth-first exploration, visited tracking, physical backtracking, and cost in moves.

    Software Engineering FundamentalsOnsite
  • WaymoMediumSoftware Engineer
    End-Picking Number Game: Can the First Player Win Under Optimal Play?

    Two players alternately take a number from either end of a row and add it to their score; decide whether the first player can finish with at least as many points as the second under optimal play. Tests minimax reasoning and memoized game-state search.

    Coding & AlgorithmsOnsite
  • WaymoHardSoftware Engineer
    Find Dictionary Words Represented by Repeated Letters

    Match dictionary words to a repeated-letter string using ordered run characters and count inequalities, with explicit stretch, duplicate, and empty-string semantics.

    Coding & AlgorithmsOnsite