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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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Showing 3661–3690 of 4616 results
- ShopifyMediumMachine Learning EngineerImplement a Capacity-Bounded Cache
This question tests the ability to implement a Least Recently Used (LRU) cache, requiring efficient O(1) time complexity for both data retrieval and insertion through the combination of a hash map and a doubly linked list.
Coding & AlgorithmsTechnical ScreenHash MapLinked ListCache - ShopifyEasySoftware EngineerImplement a multi-rover Mars controller
This question evaluates a candidate's ability to implement stateful command parsing, entity management for multiple rovers, and collision-avoidance on an unbounded 2D grid, emphasizing deterministic simulation, input/output specification, and robust handling of invalid operations.
Coding & AlgorithmsTechnical Screen - ShopifyMediumData ScientistImplement an LRU Cache
This question tests the ability to combine a hash map and a doubly linked list to achieve constant-time performance for cache operations.
Coding & AlgorithmsTechnical ScreenHash MapDoubly Linked ListCache - ShopifyEasySoftware EngineerImplement cache and gift assignment system
This two-part exercise evaluates a candidate's competence in designing efficient in-memory data structures with correct eviction semantics (bounded LRU cache with amortized O(1) operations) and in implementing randomized permutation algorithms and input/output handling for derangement-based Secret Santa assignments from CSV input.
Coding & AlgorithmsTechnical Screen - ShopifyEasyData ScientistInfer and justify non-trivial sequence patterns
This question evaluates mathematical reasoning, sequence inference, and pattern-recognition competency by asking the solver to identify governing rules and justify missing terms across numeric sequences and a small grid.
Coding & AlgorithmsTechnical Screen - ShopifyEasyData ScientistMeasure App Store success and debug funnel anomaly
This question evaluates proficiency in product analytics, instrumentation design, experimentation planning, and funnel-level diagnostic analysis for an app marketplace, and falls squarely in the Analytics & Experimentation domain for data scientist roles.
Analytics & ExperimentationTechnical Screen - ShopifyMediumData ScientistMeasure Pirate-Theme Usage and Revenue Growth Over Time
This question evaluates the ability to design time-based usage metrics and compute monthly revenue through data manipulation using SQL or Python, focusing on aggregating event and transaction records by calendar month.
Data Manipulation (SQL/Python)Technical Screen - ShopifyMediumSoftware EngineerParse a CSV and Generate a Gift Exchange
This problem tests string parsing, data validation, and algorithm design by requiring the implementation of a secret-santa style matching system from unstructured CSV data.
Software Engineering FundamentalsTechnical ScreenParsingAlgorithmsRandomization - ShopifyMediumData ScientistPerform no-calculator math accurately and fast
This question evaluates mental arithmetic, rapid estimation, numerical bounds, and familiarity with exponentials and square-root approximations within the Statistics & Math category for a Data Scientist role.
Statistics & MathTechnical Screen - ShopifyHardData ScientistPresent Piracy Trends to a PM
This question evaluates a candidate's ability to interpret time-series analytics and revenue-impact estimates, reason about measurement biases and censoring, and communicate ambiguous statistical findings to product stakeholders.
Analytics & ExperimentationTechnical Screen - ShopifyMediumSoftware EngineerScaling a Collision-Free Rover Fleet to a Million Robots
This question tests the ability to design a distributed system that manages real-time state consistency across a massive, sharded spatial grid while handling concurrency and robot movement.
System DesignTechnical ScreenDistributed SystemsConcurrencySharding - ShopifyMediumMachine Learning EngineerSimulate a rover fleet
This problem tests your ability to manage state in a 2D grid simulation, coordinate multiple entities with movement logic, and enforce collision-avoidance constraints.
Coding & AlgorithmsTechnical ScreenSimulationGridCollision Detection - ShopifyEasySoftware EngineerSimulate rover movement on a grid
This question evaluates incremental system design, agent state management on a bounded grid, and algorithmic complexity for processing movement commands in the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - ShopifyMediumSoftware EngineerTerminal-Controlled Grid Rover Simulator
Implement a warehouse rover simulation engine that processes sequential movement commands on a bounded 2D grid, handling coordinate translations, cardinal rotations, boundary limits, and multi-rover collision avoidance.
Coding & AlgorithmsTechnical Screensimulationstate-machinearrays - ShopifyMediumData EngineerUse AI Responsibly During SQL Pair Programming
Practice an AI-enabled SQL pair-programming workflow that keeps your reasoning visible. Cover requirement clarification, safe tool boundaries, incremental query design, independent edge-case testing, collaboration, and accountable debugging.
Software Engineering FundamentalsTechnical Screen - ShopifyEasyData EngineerWrite SQL for session analytics
This problem tests your ability to clean event-based log data, perform time-series aggregation, and calculate session-level metrics using SQL window functions.
Coding & AlgorithmsTechnical ScreenSQLWindow FunctionsData Cleaning - SiemensMediumTechnical Program ManagerAnswer Siemens project manager behavioral questions
Prepare for the Answer Siemens project manager behavioral questions interview question with a structured prompt, clarifying questions, answer rubric, follow-up probes, and a stronger model solution. This behavioral & leadership guide helps candidates frame assumptions, trade-offs, metrics, and role-relevant evidence without relying on generic answers.
Behavioral & LeadershipTechnical Screen - SiemensMediumMachine Learning EngineerBatch and Pad Variable-Length Vectors with Optional Final-Batch Dropping
Implement an ordered data pipeline function that partitions variable-length numerical sequences into batches, applies batch-local right padding, handles empty vectors, and optionally discards incomplete final batches.
Coding & AlgorithmsTechnical Screendata-pipelinesarraysmachine-learning - SiemensMediumMachine Learning EngineerCompare GRPO and PPO and Explain Sparse Versus Dense Rewards
This question evaluates your understanding of modern reinforcement learning post-training techniques for language models, focusing on GRPO versus standard PPO and the trade-offs between sparse outcome rewards and dense process supervision.
Machine LearningTechnical ScreenReinforcement LearningLLM Post-TrainingPPO - SiemensMediumMachine Learning EngineerDiscuss Post-Training Ownership, Failure, and Disagreement
Assesses a candidate's ability to communicate technical ownership, resilience after experimentation failures, and data-driven conflict resolution within large-scale machine learning and model post-training workflows.
Behavioral & LeadershipTechnical ScreenBehavioralPost-TrainingLLMs - SiemensMediumMachine Learning EngineerExplain SFT, DPO, PPO, and the Role of KL Regularization
Compare SFT and preference optimization, explain the DPO log-ratio objective, and clarify its relationship to PPO and KL regularization.
Machine LearningTechnical Screen - SierraMediumSoftware EngineerConversation Agent History: Paginated Fetching, Then Token-Limit Compaction
Build the message-history layer of a conversation agent: fetch the conversation page by page into one ordered list, then compact it whenever the total token count exceeds a limit by dropping the oldest messages. It tests pagination termination and ordering, running totals, and cheap removal from the front.
Software Engineering FundamentalsTechnical Screen - SierraMediumSoftware EngineerFetch Every Page from a Data API, Then Compact Records to a Token Budget
A two-part coding screen: page through a data API until it returns no more records, then, if the fetched records exceed 20,000 tokens, compact them to at most 10,000 tokens by keeping the longest contiguous run that fits. It tests loop termination, failure handling, boundary rules and an efficient way to trim data to a budget.
Software Engineering FundamentalsTechnical Screen - SierraMediumSoftware EngineerLoad a Support Chat Transcript by Pages, Then Trim to a Token Budget
Build the transcript-loading layer for a customer support chat agent: assemble a full conversation from a paginated backend into one ordered list, then trim it down whenever it grows past a token budget by dropping the oldest turns first.
Software Engineering FundamentalsTechnical Screenpaginationdata-structuresapi-design - SierraMediumSoftware EngineerPaginate an Audit-Log API, Then Compact Entries to a Byte Budget
Pull every entry out of a cursor-paginated audit-log API, then, if the entries together exceed a byte budget, keep the longest contiguous run of them (in original order) that fits. Tests correct pagination loop termination and an efficient two-pointer scan instead of re-measuring every candidate run from scratch.
Software Engineering FundamentalsTechnical Screensliding-windowpaginationapi-design - SierraHardSoftware EngineerSplit Markdown Into Header-Aware Chunks
This question evaluates string parsing, stateful text-processing, and algorithmic chunking skills, focusing on hierarchical header tracking and enforcing size constraints while preserving document order.
Coding & AlgorithmsTechnical Screen - SigmacomputingMediumSoftware EngineerBuild a Pivot Table Aggregator
This question evaluates a candidate's ability to implement data aggregation and efficient lookup structures, focusing on grouping, associative aggregations, and maintaining intermediate state for derived metrics.
Coding & AlgorithmsTechnical Screen - SigmacomputingMediumSoftware EngineerBuild a pivot table class over shirt sales records with running and grand totals
Implement a class that stores shirt sales records and builds pivot tables summing shirts sold by any row field and column field, then extend it with running totals and grand totals along both axes. It tests object-oriented structure, aggregation with dictionaries, deterministic layout, and consistency between cells and totals.
Software Engineering FundamentalsTechnical Screen - SigmacomputingEasySoftware EngineerImplement a basic pivot table with totals
This question evaluates a candidate's ability to perform in-memory data aggregation, multi-dimensional grouping, handling missing combinations, and formatted text output for pivot tables including row/column totals.
Coding & AlgorithmsTechnical Screen - SnapchatMediumData ScientistAnalyze OLS After Duplicating Every Observation
This question tests your understanding of OLS coefficient estimation and standard error calculations under the scenario of duplicate data observations.
Statistics & MathTechnical ScreenOLSLinear RegressionStatistics
Shopify
Sierra
Snapchat