ByteDance interview questions

Showing 61–90 of 160 results

• Determine Whether an Integer Is a PalindromeMedium

  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.

  ByteDanceData ScientistCoding & AlgorithmsTechnical Screen
• Determine whether squares can fitHard

  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.

  ByteDanceSite Reliability EngineerCoding & AlgorithmsTechnical Screen
• Diagnose Low CTR in an Advertising Campaign FunnelMedium

  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.

  ByteDanceData ScientistAnalytics & ExperimentationTechnical Screen
• Discuss Your Data Analytics and Causal-Inference ExperienceMedium

  Practice describing data analytics and causal-inference experience while separating descriptive insights from credible intervention effects.

  ByteDanceData ScientistBehavioral & LeadershipTechnical Screen
• Elasticsearch Deep Dive: Index Mapping Design and How the Inverted Index WorksMedium

  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.

  ByteDanceSoftware EngineerSoftware Engineering FundamentalsTechnical Screen
• Elements Occurring More Than n/3 Times in a Sorted ArrayMedium

  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.

  ByteDanceSoftware EngineerCoding & AlgorithmsTechnical Screen
• Enumerate All Simple Directed CyclesMedium

  This problem tests graph traversal skills, specifically the ability to identify unique simple cycles in a directed graph using canonical representations to avoid duplicates.

  ByteDanceSoftware EngineerCoding & AlgorithmsTechnical Screen
• Enumerate All Simple Directed PathsMedium

  This problem tests graph traversal techniques, specifically depth-first search (DFS) with backtracking to identify all unique simple paths in a directed graph.

  ByteDanceSoftware EngineerCoding & AlgorithmsTechnical Screen
• Equalize Root-to-Leaf Sums in an N-ary TreeEasy

  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.

  ByteDanceSoftware EngineerCoding & AlgorithmsTechnical Screen
• Evaluate a Migration from MySQL to MongoDBMedium

  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.

  ByteDanceSoftware EngineerSystem DesignTechnical Screen
• Evaluate an Integer Arithmetic Expression with ParenthesesMedium

  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.

  ByteDanceSoftware EngineerCoding & AlgorithmsTechnical Screen
• Explain Backend Fundamentals and AI ToolingHard

  This question tests foundational knowledge across systems engineering, database design, version control, and modern AI integration strategies.

  ByteDanceBackend EngineerSoftware Engineering FundamentalsHR Screen
• Explain Backend Infrastructure FundamentalsMedium

  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.

  ByteDanceSoftware EngineerSoftware Engineering FundamentalsTechnical Screen
• Explain CAP, indexing, locks, and logsMedium

  This question tests fundamental knowledge of distributed systems theory, database storage structures, concurrency control, and recovery mechanisms.

  ByteDanceSoftware EngineerSoftware Engineering FundamentalsTechnical Screen
• Explain Composite and Covering Indexes in MySQLMedium

  This question tests the understanding of MySQL B-tree index structures, specifically how composite index ordering affects query performance, selectivity, and disk I/O.

  ByteDanceSoftware EngineerSoftware Engineering FundamentalsTechnical Screen
• Explain GRPO for LLM Reinforcement Learning and How It Differs from PPOMedium

  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.

  ByteDanceApplied ScientistMachine LearningTechnical Screen
• Explain Kafka and Message-Queue Delivery SemanticsMedium

  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.

  ByteDanceSoftware EngineerSoftware Engineering FundamentalsTechnical Screen
• Explain LLM generational improvements, multimodal LLMs, and normalization in LLMsMedium

  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.

  ByteDanceMachine Learning EngineerMachine LearningTechnical Screen
• Explain Type I/II errors vs precision/recallMedium

  This question evaluates understanding of Type I and Type II errors in hypothesis testing and binary classification, their correspondence to false positives and false negatives, and how those concepts relate to precision and recall within the Statistics & Math domain.

  ByteDanceData ScientistStatistics & MathTechnical Screen
• Explain Virtual Memory Beyond Physical RAMMedium

  This question tests the conceptual understanding of how an operating system abstracts memory management through virtual address spaces, demand paging, and hardware-assisted translation.

  ByteDanceSoftware EngineerSoftware Engineering FundamentalsTechnical Screen
• Explain Why You Want to Change RolesMedium

  This question assesses the candidate's professional maturity, self-awareness, and ability to frame career transitions as proactive pursuits of growth rather than reactions to negative past experiences.

  ByteDanceSoftware EngineerBehavioral & LeadershipOnsite
• Explain XGBoost's Overfitting ResistanceMedium

  This question evaluates understanding of ensemble learning and model generalization, focusing on why gradient-boosted tree ensembles are often less prone to overfitting than single decision trees.

  ByteDanceMachine Learning EngineerMachine LearningTechnical Screen
• Explain a Project's Implementation and Design DecisionsMedium

  This question assesses a candidate's ability to communicate complex technical work, justify architectural trade-offs, and reflect critically on their own engineering process.

  ByteDanceSoftware EngineerBehavioral & LeadershipTechnical Screen
• Explain a promotion and key project impactMedium

  This question evaluates a candidate's ability to communicate career progression, leadership influence, ownership of high-impact projects, and aptitude for articulating measurable outcomes and trade-offs.

  ByteDanceSoftware EngineerBehavioral & LeadershipTechnical Screen
• Explain the TCP Three-Way Handshake and Its GuaranteesMedium

  Tests in-depth understanding of the TCP three-way handshake, state transitions, sequence/acknowledgment arithmetic, and failure modes such as dropped final ACKs.

  ByteDanceSoftware EngineerSoftware Engineering FundamentalsTechnical Screen
• Find Each User's Earliest Seven-Day Activity StreakMedium

  Tests your ability to identify consecutive date sequences (gaps-and-islands problem) in PostgreSQL, aggregate streaks, and filter for each user's earliest qualifying period.

  ByteDanceData ScientistData Manipulation (SQL/Python)Technical Screen
• Find Maximum Candies With Two TypesMedium

  This question evaluates algorithmic problem-solving with arrays, focusing on managing constraints on the number of distinct element types in a contiguous sequence and maintaining element frequency/state during a traversal.

  ByteDanceSoftware EngineerCoding & AlgorithmsOnsite
• Find Missing Ranges with BoundsEasy

  This question evaluates understanding of sorted array manipulation, interval arithmetic, detection of maximal missing ranges, and careful handling of boundary and edge cases in integer intervals.

  ByteDanceSoftware EngineerCoding & AlgorithmsTechnical Screen
• Find Unique One-Use Combination Sums with Negative ValuesHard

  Tests backtracking and branch-and-bound optimization when searching for subsets that sum to a target with duplicate and negative values.

  ByteDanceSoftware EngineerCoding & AlgorithmsTechnical Screen
• Find Words in a Character GridMedium

  This question evaluates algorithm design for efficient multi-word search in a character grid, testing competencies in constrained graph traversal, managing large dictionaries, and selecting data structures for efficient lookup.

  ByteDanceSoftware EngineerCoding & AlgorithmsOnsite