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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 541–570 of 9403 results
- AmazonHardSoftware EngineerDesign delayed job scheduler (LLD)
This question evaluates system design and distributed-systems competencies, including scheduling algorithms, durable persistence and recovery, concurrency control, delivery semantics, and operational concerns, and it belongs to the System Design category.
System DesignOnsite - AmazonHardSoftware EngineerDesign document-tag classes with concurrency safety
Design document-tag classes with concurrency safety 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 DesignOnsite - AmazonHardData ScientistDesign end-to-end regression for energy demand
This question evaluates a candidate's ability to design and justify an end-to-end regression system for next-day site-level energy demand forecasting, testing competencies in time-series modeling, feature engineering, regularization, evaluation metrics and SLAs, production ML pipelines, monitoring, explainability, and data privacy.
Machine LearningOnsite - AmazonMediumSoftware EngineerDesign faster delay-time computation
This question evaluates a candidate's ability to design efficient array algorithms and appropriate data structures for nearest-smaller-element queries, assessing performance, correctness with duplicates, and scalability to large inputs.
Coding & AlgorithmsOnline Assessment - AmazonHardData ScientistDesign fraud detection across channels with unknowns
This question tests the ability to design an end-to-end fraud detection system that accounts for cold-start problems, cross-channel signals, and the trade-off between customer friction and loss mitigation.
Machine LearningOnsiteFraud DetectionAnomaly DetectionGraph Neural Networks - AmazonMediumSoftware EngineerDesign globally consistent metadata service
This question tests the ability to design a globally distributed metadata service that requires strict consistency for frequent read/write operations across multiple geographic regions.
System DesignOnsiteDistributed SystemsConsistencyScalability - AmazonHardSoftware EngineerDesign in-memory threshold switcher
This question evaluates a candidate's ability to design memory-aware control systems, covering skills such as hysteresis-based thresholding, dynamic runtime reconfiguration, thread-safe concurrency, low-overhead metric sampling, event-driven state notifications, and handling multi-process and failure edge cases.
System DesignTechnical Screen - AmazonHardSoftware EngineerDesign locker allocation service
This question evaluates a candidate's understanding of stateful system design, resource allocation strategies, concurrency control, API and data modeling, and fault tolerance in the context of real-time locker assignment.
System DesignTechnical Screen - AmazonMediumSoftware EngineerDesign multi-tenant ingestion and processing platform
This question tests the ability to design a multi-tenant data platform that ensures resource fairness, performance isolation, and cost attribution at scale.
System DesignOnsiteMulti-tenancyScalabilityDistributed Systems - AmazonMediumSoftware EngineerDesign object model for an elevator system
This question evaluates object-oriented design and system-architecture skills for modeling a multi-elevator control system, including class responsibilities, interactions, request flow, and scheduling policies.
Software Engineering FundamentalsOnsite - AmazonMediumSoftware EngineerDesign pickup point planning for ride-hailing
Design a ride-hailing pickup-point planning system. Covers map snapping, candidate generation, driver and passenger routing, safety filtering, scoring objectives, app presentation, architecture, historical learning, and A/B metrics.
System DesignTechnical Screen - AmazonHardSoftware EngineerDesign real-time top-K products service
An Amazon software-engineer system-design screen: design a real-time service that ingests a stream of purchase events (customer_id, item_id, timestamp) and continuously serves the top-K most purchased items over multiple rolling windows (e.g. last 5 minutes, last 1 hour, 24 hours, and daily totals). The answer covers ingestion and partitioning, event-time windowing with watermarks, exact min-heap vs. approximate Count-Min-Sketch / Space-Saving top-K, late/duplicate/out-of-order handling, state and TTL, exactly-once fault tolerance, horizontal scaling, serving APIs, and latency-vs-accuracy trade-offs.
System DesignTechnical Screen - AmazonHardSoftware EngineerDesign ride-hailing pricing with fairness and pooling
This question evaluates system design and algorithmic skills related to real-time distributed pricing, API and data-flow architecture, carpooling logic, fairness constraints, and experimentation support.
System DesignOnsite - AmazonMediumSoftware EngineerDesign rolling-window top-K click tracker
Design rolling-window top-K click tracker 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 & AlgorithmsOnsite - AmazonHardSoftware EngineerDesign secure multi-tier cloud infrastructure
This question evaluates cloud systems design competencies including multi-tier network architecture, IP addressing and capacity planning, security controls, centralized server management, shared storage trade-offs, and identity and access integration within a production-scale virtual private cloud.
System DesignTechnical Screen - AmazonMediumData ScientistDesign student–course data models and SQL
This question evaluates data modeling, database design, and SQL proficiency—covering normalization, schema constraints, indexing, star-schema warehousing, slowly changing dimensions, partitioning strategies, and complex analytic queries—in the domain of relational databases and data warehousing (Data Manipulation/SQL).
Data Manipulation (SQL/Python)Onsite - AmazonHardApplied ScientistDesign systems for global request detection and labeling
This problem tests the architecture of a high-throughput streaming system capable of detecting anomalies in real-time, managing extreme class imbalance for labeling, and maintaining low-latency inference at a global scale.
ML System DesignOnsiteStreamingReal-time InferenceImbalanced Learning - AmazonMediumProduct ManagerDesigning AI Features for Grocery Customers: Segment, Pain Points, Prioritized Roadmap
A product sense question from Amazon product manager interviews on applying AI to make grocery shopping better for customers. It tests choosing a shopper segment, mapping the shopping journey, picking problems where AI adds real value, prioritizing a first release, and setting metrics and guardrails for prediction errors.
Product Design & StrategyOther - AmazonMediumApplied ScientistDesigning a Bayesian Classifier for Case Analysis
Tests your ability to design a probabilistic Bayesian classification system under conditions of informative missingness, non-stationary class priors, and strict calibration requirements.
Machine LearningOnsiteBayesian ModelingMissing DataModel Calibration - AmazonMediumSoftware EngineerDetect and Break a Cycle in a Singly Linked List
Tests detection and resolution of cycles in singly linked lists using two-pointer techniques with constant auxiliary space.
Coding & AlgorithmsTechnical Screenlinked-listtwo-pointersfloyds-algorithm - AmazonMediumSoftware EngineerDetect cycle in a directed graph
This question evaluates mastery of graph algorithms and graph theory concepts—specifically directed cycle detection—and assesses the ability to reason about algorithmic correctness and to analyze time and space complexity for competing approaches.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerDetect cycles in lists and graphs
This question evaluates understanding of cycle detection in linked lists and directed graphs, assessing competencies in pointer manipulation, graph traversal strategies, and reasoning about algorithmic time and space complexity within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - AmazonMediumSoftware EngineerDetect words formed by multiple dictionary parts
This question evaluates proficiency in string processing, selection and use of appropriate data structures and algorithms (hashing, tries), dynamic programming and memoization, and complexity analysis for large inputs and edge-case handling within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - AmazonMediumData ScientistDetermine Discount's Effect on Conversion Rate with A/B Testing
This interview question evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer for Determine Discount's Effect on Conversion Rate with A/B Testing states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationTechnical Screen - AmazonMediumData ScientistDetermine Length of Longest Unique Substring
This question evaluates string-processing skills and algorithmic problem-solving, including handling character uniqueness and performance considerations. Commonly asked in Coding & Algorithms interviews to assess a candidate's ability to implement efficient solutions and reason about time/space trade-offs, it targets practical application rather than purely conceptual understanding.
Coding & AlgorithmsTechnical Screen - AmazonMediumData ScientistDetermine Probability of Both Children Being Boys
Evaluates conditional probability reasoning in the classic two-children problem with different observation mechanisms. Strong answers enumerate ordered outcomes, condition correctly, and compare at-least-one, older-child, and random-child cases.
Statistics & MathTechnical Screen - AmazonMediumSoftware EngineerDetermine Rounds for Star Substring Threshold
This question evaluates string-processing and algorithmic problem-solving skills, including handling incremental updates, counting substrings impacted by character replacements, and performance-aware simulation.
Coding & AlgorithmsOnline Assessment - AmazonMediumSoftware EngineerDetermine Whether All Courses Can Be Completed
This problem tests your ability to model dependencies using a directed graph and detect cycles to determine if a set of tasks can be completed.
Coding & AlgorithmsTechnical ScreenGraphTopological SortDFS - AmazonEasySoftware EngineerDetermine Whether One Person Can Attend Every Meeting
This problem tests your ability to handle interval sorting and linear-time overlap detection to ensure no two meetings conflict.
Coding & AlgorithmsTechnical ScreenSortingIntervalsGreedy - AmazonMediumSoftware EngineerDetermine Whether Package Weights Can Be Safely Arranged
Tests array manipulation, counting techniques, and greedy or constraint-satisfaction logic to determine if an array can be permuted so no two adjacent elements sum to ten or more.
Coding & AlgorithmsTechnical ScreenGreedyCountingArray
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