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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 871–900 of 4616 results
- ByteDanceMediumSoftware EngineerDescribe your most challenging project and leadership
This question evaluates leadership, project management, technical problem-solving, decision-making, and communication competencies by probing project goals, constraints, specific responsibilities, trade-offs, and outcomes.
Behavioral & LeadershipTechnical Screen - ByteDanceMediumSoftware EngineerDesign An Ad Creative Relationship Processing System
This question tests your ability to design a distributed asynchronous processing pipeline that manages entity relationships, handles API retries, and maintains state consistency across multiple dependent components.
System DesignTechnical ScreenDistributed SystemsAsync ProcessingDatabase Schema - ByteDanceMediumMachine Learning EngineerDesign Self-Dealing Detection for Marketplaces
This question evaluates competency in machine learning system design for fraud detection, focusing on modeling buyer–seller–item–transaction relationships, feature engineering across graph, temporal, behavioral and account-linking signals, and production concerns; it is in the ML System Design domain and emphasizes practical application and system-level architecture over purely theoretical concepts. It is commonly asked to assess a candidate’s ability to reason about data collection and labeling, model and rule trade-offs, evaluation metrics, scalability and deployment trade-offs when detecting coordinated or self-dealing activity in marketplace environments.
ML System DesignTechnical Screen - ByteDanceMediumSoftware EngineerDesign a C++ Shared-Ownership Pointer Library
Explain shared-pointer control blocks, copy and move semantics, lifetime invariants, exception safety, and the limits of reference counting.
Software Engineering FundamentalsTechnical Screen - ByteDanceHardSoftware EngineerDesign a Configurable Order Validator with DAG Dependencies
This problem tests your ability to design a flexible, extensible rule-processing engine that handles sequential and interdependent validation logic.
Software Engineering FundamentalsTechnical ScreenDesign PatternsDAGTopological Sort - ByteDanceMediumSoftware EngineerDesign a Monitoring Dashboard with Explicit Latency Goals
Design a monitoring dashboard that separates data freshness from query latency, with ingestion, rollups, browser updates, and stale-data handling.
System DesignTechnical Screen - ByteDanceMediumSoftware EngineerDesign a RAG-Based Agent System
This question tests the ability to architect a scalable Retrieval-Augmented Generation (RAG) system that handles document indexing, retrieval, and multi-step reasoning while maintaining low latency and data freshness.
ML System DesignTechnical ScreenRAGLLMSystem Design - ByteDanceHardSoftware EngineerDesign a Synchronized Live Comment Overlay
Design a live comment overlay that stays synchronized with a video during live viewing, replay, seeking, and reconnects. Explore timeline semantics, stable ordering, scalable fanout, replay queries, moderation, backpressure, and graceful degradation during traffic bursts.
System DesignTechnical Screen - ByteDanceMediumSoftware EngineerDesign a Ticket Booking System for High-Demand On-Sales Without Overselling
A system design question about a ticket booking system for high-demand on-sales. It probes how to absorb the traffic spike when sales open with load balancing, waiting rooms and rate limiting, and how to manage inventory with holds, payment-timeout release and consistent cache and database updates so that no ticket is ever sold twice.
System DesignTechnical Screen - ByteDanceMediumSenior SDE, Quality Platform & AI Test AutomationDesign an Agent-Orchestrated QA Pipeline from Requirements to Test Report
Design an end-to-end multi-agent QA platform that autonomously transforms feature requirements into validated test cases, synthetic data, executable test scripts, and traceable execution reports with human-in-the-loop oversight.
ML System DesignTechnical ScreenAI AgentsTest AutomationCI/CD - ByteDanceHardSoftware EngineerDesign an E-Commerce Platform with Reliable Checkout
Design an e-commerce platform with searchable catalogs, carts, atomic inventory reservations, idempotent checkout, payment recovery, and reliable order state.
System DesignTechnical Screen - ByteDanceMediumMachine Learning EngineerDesign an Enterprise Tool-Using Agent
This question evaluates a candidate's ability to design production-grade LLM agents that integrate external tools, manage long-running and branching workflows, persist complex state, and ensure safety, observability, and reliable evaluation in enterprise settings.
ML System DesignTechnical Screen - ByteDanceMediumSoftware EngineerDesign an RBAC Relational Schema
This problem tests your ability to design a normalized relational database schema that implements Role-Based Access Control (RBAC) to support hierarchical users, roles, and resource-level permissions.
System DesignTechnical ScreenSQLDatabase SchemaRBAC - ByteDanceMediumData ScientistDetermine Whether an Integer Is a Palindrome
This problem tests your ability to manipulate integers mathematically to detect palindromic sequences without converting the number into a string, requiring careful handling of edge cases and integer overflow.
Coding & AlgorithmsTechnical ScreenMathAlgorithmsInteger Manipulation - ByteDanceHardSite Reliability EngineerDetermine whether squares can fit
This question evaluates spatial reasoning, combinatorial packing, and constraint-satisfaction skills in the context of placing integer-aligned squares within an m x n rectangle.
Coding & AlgorithmsTechnical Screen - ByteDanceMediumData ScientistDiagnose Low CTR in an Advertising Campaign Funnel
Prepare for a product analytics interview by diagnosing below-average advertising CTR from limited campaign-level funnel metrics. The question tests metric interpretation, uncertainty, evidence-versus-hypothesis discipline, and how to plan useful follow-up analysis.
Analytics & ExperimentationTechnical Screen - ByteDanceMediumData ScientistDiscuss Your Data Analytics and Causal-Inference Experience
Practice describing data analytics and causal-inference experience while separating descriptive insights from credible intervention effects.
Behavioral & LeadershipTechnical Screen - ByteDanceMediumSoftware EngineerElasticsearch Deep Dive: Index Mapping Design and How the Inverted Index Works
From a TikTok backend intern interview: explain how the Elasticsearch index and field mappings in a resume project were designed and why, then explain how an inverted index works. It tests whether a candidate understands the search technology they list, from mapping trade-offs to how queries are answered.
Software Engineering FundamentalsTechnical Screen - ByteDanceMediumSoftware EngineerElements Occurring More Than n/3 Times in a Sorted Array
This problem tests your ability to optimize frequency counting in a sorted array by leveraging binary search to achieve logarithmic time complexity, rather than a linear scan.
Coding & AlgorithmsTechnical ScreenBinary SearchArraysSorting - ByteDanceMediumSoftware EngineerEnumerate All Simple Directed Cycles
This problem tests graph traversal skills, specifically the ability to identify unique simple cycles in a directed graph using canonical representations to avoid duplicates.
Coding & AlgorithmsTechnical ScreenGraphsDFSBacktracking - ByteDanceMediumSoftware EngineerEnumerate All Simple Directed Paths
This problem tests graph traversal techniques, specifically depth-first search (DFS) with backtracking to identify all unique simple paths in a directed graph.
Coding & AlgorithmsTechnical ScreenGraphDFSBacktracking - ByteDanceEasySoftware EngineerEqualize Root-to-Leaf Sums in an N-ary Tree
Find the minimum total increments needed to make every root-to-leaf path in a nonnegative-valued N-ary tree have the same sum. The parent-array input may contain 200,000 nodes and a depth beyond Python's recursion limit.
Coding & AlgorithmsTechnical Screen - ByteDanceMediumSoftware EngineerEvaluate a Migration from MySQL to MongoDB
Evaluate whether a MySQL-backed service should migrate to MongoDB using its actual workload and correctness needs. Compare relational and document models, joins and transactions, then outline a dual-run migration, rollback plan, and measurements that would prove an improvement.
System DesignTechnical Screen - ByteDanceMediumSoftware EngineerEvaluate an Integer Arithmetic Expression with Parentheses
This problem tests the ability to evaluate arithmetic expressions containing addition, subtraction, multiplication, and division, while correctly handling parentheses, operator precedence, and unary operators without using recursion.
Coding & AlgorithmsTechnical ScreenStackMathParsing - ByteDanceMediumSoftware EngineerExplain Backend Infrastructure Fundamentals
This question tests your understanding of Kafka's distributed messaging architecture, specifically how message distribution, ordering guarantees, and consumer scalability interact during consumer group operations.
Software Engineering FundamentalsTechnical ScreenKafkaDistributed SystemsMessaging - ByteDanceMediumSoftware EngineerExplain CAP, indexing, locks, and logs
This question tests fundamental knowledge of distributed systems theory, database storage structures, concurrency control, and recovery mechanisms.
Software Engineering FundamentalsTechnical ScreenDistributed SystemsDatabasesConcurrency - ByteDanceMediumSoftware EngineerExplain Composite and Covering Indexes in MySQL
This question tests the understanding of MySQL B-tree index structures, specifically how composite index ordering affects query performance, selectivity, and disk I/O.
Software Engineering FundamentalsTechnical ScreenMySQLDatabaseB-Tree - ByteDanceMediumApplied ScientistExplain GRPO for LLM Reinforcement Learning and How It Differs from PPO
An ML question asking you to explain Group Relative Policy Optimization (GRPO) for fine-tuning large language models with reinforcement learning. It tests your grasp of group-normalized advantages, the clipped objective with a KL penalty, the contrast with PPO and its value model, and common failure modes.
Machine LearningTechnical Screen - ByteDanceMediumSoftware EngineerExplain Kafka and Message-Queue Delivery Semantics
This question tests your understanding of distributed messaging patterns, focusing on the architectural differences between log-based and queue-based systems and the trade-offs involved in ensuring reliable message delivery.
Software Engineering FundamentalsTechnical ScreenKafkaDistributed SystemsMessage Queues - ByteDanceMediumMachine Learning EngineerExplain LLM generational improvements, multimodal LLMs, and normalization in LLMs
Three conceptual LLM questions: the main improvements across generations of a model family as described in technical reports, how multimodal image-and-text models are built and trained, and why modern LLMs use layer normalization or RMSNorm with pre-norm placement instead of batch normalization.
Machine LearningTechnical Screen