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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.
- 9403
- Questions
- 546
- Companies
- 11
- Topics
- 8
- Languages
Showing 3751–3780 of 4616 results
- SnowflakeMediumSoftware EngineerCount the Nodes of a Process Tree Using Only Asynchronous Messages
Each node of a tree is a separate process that can only send asynchronous messages and block on receive; write the logic that lets the root learn how many nodes exist. Follow-ups cover lost and duplicated messages, retries and idempotency, and how to structure a result that may be incomplete.
Software Engineering FundamentalsTechnical Screen - SnowflakeMediumSoftware EngineerDecide Whether Repeatedly Summing Squared Digits Reaches 1
Starting from a positive integer, repeatedly replace it by the sum of the squares of its digits and decide whether the sequence reaches 1 or falls into a cycle. It tests cycle detection on an implicit sequence and reasoning about why the values stay bounded.
Coding & AlgorithmsTechnical Screen - SnowflakeMediumSoftware EngineerDecide Whether an Undirected Graph Can Be Colored with Three Colors
Given an undirected graph with up to fifteen nodes, decide whether every node can receive one of three colors so that no edge joins two nodes of the same color. It tests backtracking search with pruning and reasoning about odd cycles and cliques.
Coding & AlgorithmsTechnical Screen - SnowflakeMediumSoftware EngineerDeep-Copy a Linked List Whose Nodes Also Carry a Random Pointer
Return a deep copy of a singly linked list in which every node also has a random pointer to any node or to nothing, so that the copy shares no node with the original. It tests mapping original nodes to copies, pointer wiring and constant-space alternatives.
Software Engineering FundamentalsTechnical Screen - SnowflakeMediumSoftware EngineerDeep-Copy a Linked List with Random Pointers
Implement a deep copy of a linked list where each node has both a next pointer and an arbitrary random pointer, ensuring all reachable nodes and relationships are replicated without modifying the original list.
Coding & AlgorithmsTechnical ScreenLinked ListHash TableGraph - SnowflakeMediumSoftware EngineerDelete the Fewest Tree Nodes to Meet a Height Limit
Find a minimum-cardinality set of tree-node deletions under child-promotion semantics using height-budget dynamic programming and explicit solution reconstruction.
Coding & AlgorithmsTechnical Screen - SnowflakeMediumData ScientistDescribe navigating ambiguous, repetitive questioning
This question evaluates a Data Scientist's skills in stakeholder communication, ambiguity management, diagnostic reasoning to identify misaligned goals or definitions, adaptive framing between technical and plain-language explanations, trade-off analysis under time pressure, and delivering measurable outcomes.
Behavioral & LeadershipTechnical Screen - SnowflakeMediumSoftware EngineerDesign a Cron Job Scheduler
This question evaluates skills in designing reliable distributed schedulers, including durable state modeling, concurrency and race-condition reasoning, idempotency, and fault-tolerant handoff semantics, and is commonly asked to assess a candidate's ability to guarantee correctness and coordination when multiple replicas must manage recurring job triggers. Categorized under system design and distributed systems with overlap into data modeling and consistency, it emphasizes practical application of architectural and operational trade-offs rather than purely theoretical concepts.
System DesignTechnical Screen - SnowflakeMediumSoftware EngineerDesign a Distributed Job Scheduler with Cron, Pause and Resume
Design a job scheduler service that runs one-time and cron jobs, supports pausing and resuming, and dispatches work to an unlimited pool of workers. It tests due-job indexing, claim and lease protocols, pause semantics, at-least-once execution with idempotency, and handling top-of-the-hour spikes.
System DesignTechnical Screen - SnowflakeMediumSoftware EngineerDesign a Geolocation Search Service
This question tests your ability to design a scalable spatial indexing system capable of performing range-based queries (e.g., 'find all points of interest within 5km') while maintaining high availability and low latency.
System DesignTechnical ScreenGeolocationIndexingScalability - SnowflakeHardSoftware EngineerDesign a REST API Abstraction Layer
This question evaluates system design and API design competencies, focusing on creating a REST API abstraction layer and internal SDK that address cross-cutting concerns like reliability, observability, security, versioning, and contract/interface modeling.
System DesignTechnical Screen - SnowflakeMediumSoftware EngineerDesign a Shared User Quota Service That Never Overdraws
Design a quota service that several services draw from for each user, where the balance must never be overdrawn under highly concurrent requests and must stay strongly consistent. It tests atomic conditional updates, reserve-and-commit APIs with idempotency, replication choices, and scaling a single hot user's quota.
System DesignTechnical Screen - SnowflakeHardSoftware EngineerDesign a Thread-Safe Multi-Rule Rate Limiter
This problem tests the ability to design a thread-safe, flexible rate-limiting system that handles multiple constraints, atomic permit management, and graceful error handling.
Software Engineering FundamentalsTechnical ScreenConcurrencyRate-LimitingThread-Safety - SnowflakeHardSoftware EngineerDesign a distributed system end-to-end
This question evaluates a candidate's ability to design scalable, multi-tenant distributed analytics platforms, testing competencies in distributed systems architecture, data layout and storage, query planning and execution, metadata management, consistency and replication strategies, fault tolerance, observability, and capacity planning.
System DesignTechnical Screen - SnowflakeMediumSoftware EngineerDesign a distributed tree node counter
Design a distributed tree node counter 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 - SnowflakeHardSoftware EngineerDesign a multi-tenant quota system
This question evaluates a candidate's ability to design a global multi-tenant quota service, testing competencies in distributed systems, data consistency, concurrency control, API and storage modeling, and scalability within the System Design domain.
System DesignTechnical Screen - SnowflakeHardData ScientistDesign an A/B test for ML model launch
This question evaluates a data scientist's competence in experimental design, statistical power analysis, sequential monitoring, covariate adjustment (e.g., CUPED), and practical operational concerns like guardrails, interference, and ramping for ML model launches.
Analytics & ExperimentationTechnical Screen - SnowflakeMediumSoftware EngineerDesign an Audit Logs Service
Tests the ability to design an immutable, highly available, multi-tenant audit logging service that supports high-throughput ingestion and tamper-evident storage while providing fast, tenant-scoped querying.
System DesignTechnical ScreenDistributed SystemsSecurityMulti-Tenancy - SnowflakeMediumSoftware EngineerDesign an Interactive Query Execution Notebook
Tests your ability to design an asynchronous, scalable system for executing interactive SQL queries and streaming execution state and tabular results back to web clients.
System DesignTechnical Screensystem-designdistributed-systemsapi-design - SnowflakeMediumSoftware EngineerDesign an in-memory filesystem and circular queue
This question evaluates a candidate's skills in data-structure and algorithm design, API specification, correctness reasoning, and time/space complexity analysis within the Coding & Algorithms domain by combining an in-memory hierarchical filesystem design with a fixed-size circular queue implementation.
Coding & AlgorithmsTechnical Screen - SnowflakeMediumSoftware EngineerDesign an object store with deduplication
This question evaluates a candidate's ability to design scalable, durable object storage systems with deduplication, touching on storage architecture, data modeling, metadata management, consistency, and garbage collection.
System DesignTechnical Screen - SnowflakeHardData ScientistDesign and validate a cost-sensitive classifier
This question evaluates competence in cost-sensitive binary classification, handling delayed and imbalanced labels, calibration and decision-threshold selection, distributional-drift detection, monitoring, and low-latency deployment within the Machine Learning / Data Science domain.
Machine LearningTechnical Screen - SnowflakeMediumSoftware EngineerDesign error detection and propagation algorithms
This question evaluates algorithm design and complexity-analysis skills across search and graph problems, specifically log search for first-error detection, reachability and failure propagation in directed service dependency graphs, and longest-path reasoning under cycle or DAG assumptions.
Coding & AlgorithmsTechnical Screen - SnowflakeHardSoftware EngineerDesign transactional in-memory key-value store
This question evaluates understanding of in-memory key–value store semantics, transactional and nested transaction behavior, and practical competencies in hash-based data structures and thread-safety for concurrent access.
Coding & AlgorithmsTechnical Screen - SnowflakeHardSoftware EngineerDesign under vague distributed requirements
This question evaluates expertise in distributed system architecture, metadata and schema management, transactional DDL semantics, consistency and replication strategies, API and data-model design, multi-tenant isolation, observability, security, and capacity planning.
System DesignTechnical Screen - SnowflakeMediumSoftware EngineerDetermine Whether an Undirected Graph Is 3-Colorable
This problem tests knowledge of graph theory, specifically constraint satisfaction, and the ability to implement a backtracking algorithm to solve NP-complete problems on small constraints.
Coding & AlgorithmsTechnical ScreenGraphBacktrackingRecursion - SnowflakeMediumSoftware EngineerEffective Permissions in an Inheritance DAG with Allow and Deny Lists
Nodes of a directed acyclic graph carry allow and deny permission lists that are inherited along its edges; compute every node's final permissions. It tests topological processing, settling an unstated conflict rule between allow and deny, cycle detection and incremental updates.
Software Engineering FundamentalsTechnical Screen - SnowflakeMediumSoftware EngineerEvaluate an Arithmetic Expression with Parentheses, Unary Minus and Four Operators
Evaluate an arithmetic expression string with non-negative integers, addition, subtraction, multiplication, division truncating toward zero, parentheses and a unary minus. It tests tokenizing, operator precedence, left-to-right evaluation and deeply nested parentheses without eval.
Coding & AlgorithmsTechnical Screen - SnowflakeMediumSoftware EngineerEvaluate arithmetic expression with variables
This question evaluates implementation skills for a linear-time expression parser and evaluator, covering tokenization, variable substitution, operator precedence and associativity (including unary +/−), parentheses handling, integer arithmetic semantics (division truncation), error detection, and adherence to O(L) time and space constraints.
Coding & AlgorithmsTechnical Screen - SnowflakeMediumFrontend EngineerExplain React classes, lifecycle, and hooks
This question assesses the evolution of React component patterns, specifically focusing on the transition from class-based lifecycles to functional hooks, and the management of stateful side effects.
Software Engineering FundamentalsTechnical ScreenReactFrontendJavaScript
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