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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
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- 11
- Topics
- 8
- Languages
Showing 1831–1860 of 9403 results
- ByteDanceMediumSoftware EngineerFind Words in a Character Grid
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.
Coding & AlgorithmsOnsite - ByteDanceHardSoftware EngineerFind the Best Word for a Query Suffix
This problem tests your ability to efficiently query a dictionary for the longest word ending with a specific suffix, requiring optimal data structure usage for prefix/suffix operations.
Coding & AlgorithmsTechnical ScreenTrieString ManipulationData Structures - ByteDanceMediumSoftware EngineerFind the Earliest Contiguous Removal That Balances Index Sums
This problem tests array manipulation, prefix sums, and index tracking while handling state changes caused by subarray removal.
Coding & AlgorithmsTechnical ScreenArrayPrefix SumOptimization - ByteDanceMediumSoftware EngineerFind the Minimum Window Containing a Multiset of Characters
This problem tests your ability to use the two-pointer sliding window technique combined with a frequency map to identify the smallest valid substring efficiently.
Coding & AlgorithmsOnsiteSliding WindowHash MapStrings - ByteDanceMediumSoftware EngineerFind the N-th Highest Bid in an Auction Log Without a Heap
Given an unordered list of auction bids, return the n-th highest one, treating two equal bid amounts as distinct entries, while a heap-based solution is off the table. Tests selection algorithms faster than full sorting, correct handling of duplicate values, and justifying the achieved time complexity.
Coding & AlgorithmsOnsitequickselectarraysselection - ByteDanceMediumData ScientistFind top-paid employee per department
This problem tests your ability to perform group-wise filtering and ranking using window functions or joins to extract top-performing records within categories.
Data Manipulation (SQL/Python)Technical ScreenSQLWindow FunctionsAggregation - ByteDanceMediumSite Reliability EngineerGenerate combinations and permutations
This problem tests your ability to implement recursive backtracking algorithms to generate all possible permutations and combinations of a given set of distinct integers.
Coding & AlgorithmsTechnical ScreenRecursionBacktrackingCombinatorics - ByteDanceMediumSoftware EngineerHand-Write a Multi-Head Attention Layer: Projections, Head Splitting and Masking
Write a multi-head attention layer from scratch: project queries, keys and values, split them into heads, apply scaled dot-product attention with optional padding or causal masks, and merge the heads. It tests tensor shape discipline, numerical stability, and the cost of attention as sequence length grows.
Machine LearningOnsite - ByteDanceMediumSoftware EngineerHandle Communication Difficulty and Ambiguity on a Project
Use a concrete project to show how you made ambiguous decisions and communication friction visible, aligned owners and deadlines, managed residual uncertainty, and protected delivery.
Behavioral & LeadershipTechnical Screen - ByteDanceHardSoftware EngineerHandle Island Counting When the Grid Does Not Fit in Memory
This problem tests the ability to adapt graph traversal algorithms (like BFS or DFS) to scenarios where the dataset exceeds primary memory, requiring disk-based processing or tiling strategies.
Software Engineering FundamentalsTechnical ScreenGraph AlgorithmsSystem DesignExternal Memory - ByteDanceMediumSite Reliability EngineerHow You Build Service Stability and Troubleshoot Production Incidents
Tests an SRE candidate's ability to design proactively stable services and execute structured, mitigation-first production incident management under high-throughput conditions.
Software Engineering FundamentalsTechnical ScreenSREIncident ManagementObservability - ByteDanceMediumProduct ManagerHow do you prioritize requirements
Explain how a TikTok platform PM generates, evaluates, prioritizes, and communicates requirements. The answer covers stakeholder intake, RICE scoring, platform leverage, technical debt, compliance, opportunity cost, internal-user metrics, and roadmap tradeoffs.
Product / Decision MakingTechnical Screen - ByteDanceHardData ScientistHow to deploy and tune multimodal models?
A six-part ByteDance data scientist onsite ML interview covering deploying and tuning multimodal models under GPU/VRAM, compute, and latency constraints; designing fast video retrieval over precomputed captions and embeddings with ANN and hybrid reranking; and deep-learning fundamentals — overfitting detection and mitigation, dropout and inverted-dropout scaling, normalization layers (BatchNorm/LayerNorm/GroupNorm/InstanceNorm/RMSNorm), and reinforcement learning for LLM post-training (RLHF). It tests practical systems tradeoffs alongside theoretical foundations across ML systems, retrieval, and reinforcement learning.
Machine LearningOnsite - ByteDanceHardSite Reliability EngineerHow to triage slow service alerts
This question evaluates operational troubleshooting and incident management competencies — system observability, severity assessment, blast-radius and user-impact analysis, dependency and performance diagnostics, mitigation decision-making, and incident communication.
Software Engineering FundamentalsTechnical Screen - ByteDanceMediumData ScientistHow would you choose a classification threshold?
This question evaluates understanding of threshold selection for probabilistic binary classifiers, testing competencies in validation-set decision threshold choice, cost-sensitive trade-offs between false positives and false negatives, effects of class imbalance, and probability calibration.
Machine LearningTechnical Screen - ByteDanceHardSoftware EngineerImplement Expiring LRU Cache
This question evaluates skill in designing and implementing efficient in-memory caching data structures, testing understanding of LRU eviction, per-entry TTL expiration, and the use of hash maps and linked lists for O(1) operations.
Coding & AlgorithmsTechnical Screen - ByteDanceMediumApplied ScientistImplement Multi-Head Attention from Scratch
An ML coding question asking you to implement multi-head attention from scratch in NumPy or PyTorch, from the query, key and value projections to the output projection. It tests tensor shape handling, scaled dot-product attention, masking, numerical stability and complexity analysis.
Machine LearningTechnical Screen - ByteDanceMediumSoftware EngineerImplement Sliding Windows and LRU Cache
This question evaluates algorithmic problem-solving and data-structure design, testing sliding-window and 2D submatrix reasoning for maximizing contiguous ones with bounded flips and the design of an LRU cache that enforces O(1) get/put semantics.
Coding & AlgorithmsOnsite - ByteDanceMediumSite Reliability EngineerImplement Sorted Search and Array Updates
This question evaluates proficiency in array manipulation and fundamental algorithmic techniques—specifically binary search for sorted arrays, digit-wise arithmetic with carry handling, and in-place stable reordering—within the Coding & Algorithms domain and with attention to time and space complexity.
Coding & AlgorithmsTechnical Screen - ByteDanceHardMachine Learning EngineerImplement a Transformer Decoder from Scratch Without Starter Code
Implement a transformer decoder from scratch with no starter code in about 30 minutes, including embeddings, masked multi-head self-attention, feed-forward layers, residual connections and layer normalization. Tests tensor-shape fluency, causal masking and hands-on deep learning coding for a machine learning engineer interview.
Machine LearningTechnical Screen - ByteDanceHardSoftware EngineerImplement a binary min-heap and use it to order courses with prerequisites
A two-part coding question: implement a binary min-heap with push, pop, peek and linear-time construction without library helpers, then use it to order courses with prerequisites, always taking the smallest-numbered available course and detecting circular prerequisites. Tests heap mechanics and dependency ordering.
Software Engineering FundamentalsTechnical Screen - ByteDanceMediumSoftware EngineerImplement an Idempotent Versioned Database Update
Tests your ability to design and implement a concurrency-safe, idempotent record update operation using optimistic concurrency control and deduplication keys.
Software Engineering FundamentalsTechnical ScreenDistributed SystemsConcurrencyAPI Design - ByteDanceMediumSoftware EngineerImplement an LRU Cache
This problem tests your ability to combine a hash map and a doubly linked list to achieve constant-time performance for cache operations.
Coding & AlgorithmsTechnical ScreenHash MapDoubly Linked ListDesign - ByteDanceEasyData ScientistImplement several OA simulation problems
This set of problems evaluates skills in string processing, memory simulation and allocation logic, and online data-structure maintenance for dynamic contiguous segment counting, testing algorithmic design and attention to stateful invariants.
Coding & AlgorithmsOnline Assessment - ByteDanceHardData ScientistImplement stack variants and upward path sum
A four-part ByteDance Data Scientist onsite coding question: implement an O(1) MinStack, a MaxStack with peekMax/popMax, a streaming median finder, and a binary-tree upward (node-to-ancestor) path-sum check. It tests data-structure augmentation, streaming order statistics, and prefix-sum tree reasoning.
Coding & AlgorithmsOnsite - ByteDanceMediumProduct ManagerImprove TikTok ads and moderation
Answer TikTok PM strategy questions on content ecosystem comparison, less commercial ads, moderation efficiency, and AI moderation evaluation. The solution covers relevance, pacing, creative quality, risk-based queues, human oversight, precision, recall, appeals, and trust metrics.
Product Design & StrategyTechnical Screen - ByteDanceMediumSoftware EngineerInfer an Alien Alphabet from Sorted Words
This problem tests graph theory knowledge, specifically topological sorting using Kahn's algorithm or DFS, applied to dependency resolution between characters.
Coding & AlgorithmsTechnical ScreenGraphTopological SortBFS - ByteDanceHardData ScientistInterpret and validate regression with interactions
This question evaluates understanding of regression modeling with interaction terms, binary outcome models and odds/marginal-effect interpretation, causal inference concepts like endogeneity and instrumental variables, model diagnostics and standard-error choices, and count-data modeling.
Statistics & MathTechnical Screen - ByteDanceMediumSoftware EngineerIntersect Two Sorted Lists of Disjoint Intervals
Intersect two sorted lists of disjoint closed intervals in linear time, retaining one-point endpoint overlaps and advancing whichever current interval ends first.
Coding & AlgorithmsTechnical Screen - ByteDanceHardSoftware EngineerLeast Frequently Used (LFU) Cache
This problem tests the ability to design an O(1) time complexity cache that evicts the least frequently used items, using recency as a tie-breaker.
Coding & AlgorithmsOnsiteHash MapLinked ListData Structures