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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 8461–8490 of 9403 results
- TikTokHardMachine Learning EngineerImplement local maxima, bagging, and k-means
This problem tests your ability to implement a sliding window peak detector, a bootstrapping ensemble sampler, and a centroid-based clustering algorithm from scratch.
Coding & AlgorithmsOnline AssessmentAlgorithmsClusteringEnsemble Learning - TikTokMediumData ScientistImplement streaming SRM detector with late events
This question evaluates proficiency in stateful stream processing, statistical anomaly detection for sample ratio mismatch, and scalable system design concerns such as deduplication, late/out-of-order event handling, real-time aggregation, chi-square testing with Yates correction, bot-rate mitigation, sharding, and replay validation.
Coding & AlgorithmsHR Screen - TikTokMediumData ScientistImprove TikTok's Algorithm for Diverse Content Discovery
Evaluates product feedback and experiment design for improving content discovery in TikTok-style feeds. Strong answers propose specific improvements, justify impact, define metrics, and plan experiments with guardrails.
Analytics & ExperimentationOnsite - TikTokHardSoftware EngineerImprove and measure service performance
This question evaluates performance engineering and observability skills—specifically SLIs/SLOs definition, instrumentation and profiling, load-testing, bottleneck identification, and optimization trade-offs for stateless HTTP microservices.
System DesignTechnical Screen - TikTokMediumSoftware EngineerIntroduce yourself and explain your project
This question evaluates communication, ownership, leadership, and impact articulation by prompting a personal introduction and a focused project narrative covering business context, responsibilities, delivered features, and key challenges.
Behavioral & LeadershipTechnical Screen - TikTokMediumData ScientistInvestigate Traffic Distribution Impact on Retention Decrease
Evaluates A/B test diagnostics for a retention decrease after a button-color change. Strong answers check allocation, balance, logging, maturation, statistical robustness, segments, and decision criteria before blaming treatment.
Analytics & ExperimentationTechnical Screen - TikTokEasySoftware EngineerInvestigate an iOS Memory Failure
Tests understanding of iOS memory management fundamentals, including differentiating Jetsam OOM events from fatal access exceptions, pinpointing retain cycles and memory growth, and using Xcode profiling tools to confirm fixes.
Software Engineering FundamentalsTechnical ScreeniOSSwiftMemory Management - TikTokHardData ScientistInvestigate visit–report correlation causality
This question evaluates a candidate's competency in causal inference, experimental design, diagnostic analytics, and statistical modeling with ad-level observational data.
Analytics & ExperimentationTechnical Screen - TikTokMediumData ScientistInvestigating Correlation Between Ad Visits and Reports
This question evaluates a data scientist's competency in operational analytics, including defining and aggregating metrics in SQL and applying causal reasoning to interpret correlations between ad exposures and user reports.
Data Manipulation (SQL/Python)Technical Screen - TikTokMediumProduct ManagerLogin Flow Critique, Feature Improvement & Data Privacy
Practice a TikTok product case covering login-flow critique, feature improvement, and data safeguards. The solution evaluates pre-login value, auth friction, OTP and account recovery issues, proposes Smart Collections, defines experiment metrics, and outlines privacy, security, and data-integrity controls.
Product / Decision MakingTechnical Screen - TikTokMediumData ScientistMaximize Distinct Purchases Within Budget Constraints
This question evaluates understanding of selection and optimization under budget constraints, algorithmic efficiency, and the ability to implement correct logic for maximizing the number of distinct items purchased.
Coding & AlgorithmsOnline Assessment - TikTokMediumSoftware EngineerMaximize min+max of contiguous subarray
This question evaluates understanding of array algorithms and competency in identifying and reasoning about minimum and maximum values within contiguous subarrays, emphasizing extremal value handling.
Coding & AlgorithmsTechnical Screen - TikTokMediumData ScientistMaximize products bought under budget
This question evaluates algorithmic problem-solving skills including sorting, prefix-sum accumulation, binary search, greedy selection, careful tie-breaking for lexicographic order, and complexity analysis.
Coding & AlgorithmsOnline Assessment - TikTokHardData ScientistMeasure Billboard Campaign Effectiveness and Engagement Quantification
Evaluates offline marketing measurement for a billboard campaign, including how to define attributable engagement, estimate exposed population, and forecast incremental traffic, sign-ups, retention, revenue, and ROI. Strong answers use geo-lift, matched markets, or synthetic controls rather than direct attribution alone.
Analytics & ExperimentationOnsite - TikTokMediumProduct ManagerMotivation & Cross-Functional Collaboration
Practice TikTok PM phone-screen answers for motivation, current-role impact, and cross-functional collaboration. The guide gives concise structures, TikTok-specific product angles, STAR examples, metric framing, trade-off communication, stakeholder alignment, and common mistakes to avoid.
Behavioral & LeadershipTechnical Screen - TikTokMediumData ScientistOptimize Station Sequence for Maximum Car Output in Simulation
This question evaluates a candidate's skills in scheduling and throughput optimization, including queue management and simulation-based performance analysis within constrained buffering and station sequencing.
Coding & AlgorithmsOnsite - TikTokMediumSoftware EngineerParse a nested list from a string
This problem tests your ability to parse recursive nested structures using stack-based iteration or recursion and string manipulation.
Coding & AlgorithmsTechnical ScreenRecursionStackParsing - TikTokMediumSoftware EngineerParse chemical formula with multipliers
Parse chemical formula with multipliers 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 & AlgorithmsTechnical Screen - TikTokEasySoftware EngineerPlan QA testing for a new feature
This problem tests your ability to structure a comprehensive quality assurance strategy for a social media feature, balancing functional testing, edge cases, and automation.
Software Engineering FundamentalsTechnical ScreenQATesting StrategySystem Design - TikTokMediumBackend Software EngineerProcess LRU Cache Operations
Implement an LRU cache through a deterministic stream of put and get operations, including updates, misses, and eviction order. The prompt defines an exact portable function contract and examples suitable for a later four-language console handoff.
Coding & AlgorithmsOnsite - TikTokHardData ScientistProve conversion ads value via incrementality
This question tests your ability to design a robust incrementality experiment to measure the causal impact of advertising, accounting for selection bias and interference.
Analytics & ExperimentationTechnical ScreenCausal InferenceA/B TestingAds Measurement - TikTokHardData ScientistRank factors for TikTok market entry
This Behavioral & Leadership interview prompt for a Data Scientist evaluates cross-functional prioritization, market-entry decision-making, experimental design and measurement, commercial analytics, and regulatory risk assessment within product and growth strategy.
Behavioral & LeadershipTechnical Screen - TikTokMediumSoftware EngineerReconstruct a tree from two traversals
Reconstruct a tree from two traversals 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 & AlgorithmsTechnical Screen - TikTokHardData ScientistReflect on a challenging project you led
This question evaluates leadership, cross-functional influence, and applied data science competencies—focusing on ambiguity management, causal measurement, hypothesis testing, and driving product decisions.
Behavioral & LeadershipTechnical Screen - TikTokHardSoftware EngineerRemove the Fewest Overlapping Intervals
Tests greedy interval scheduling and sorting techniques to find the minimum number of intervals to remove so that no remaining intervals overlap.
Coding & AlgorithmsOnsiteGreedySortingIntervals - TikTokMediumData ScientistResolve Stakeholder Conflicts: Actions and Outcomes Explained
Evaluates behavioral stakeholder-conflict storytelling for data scientists delivering products or experiments. Strong answers use STAR, show empathy, structure trade-offs, drive decisions, and quantify outcomes.
Behavioral & LeadershipOnsite - TikTokMediumSoftware EngineerRestore Every Valid IP Address
Implement a backtracking algorithm to partition a digit string into four valid IPv4 octets, adhering to numerical range and leading-zero constraints.
Coding & AlgorithmsTechnical ScreenBacktrackingStringRecursion - TikTokMediumData ScientistSQL Queries and Analysis on Bad Advertisers
This question evaluates SQL query writing, metric definition and normalization, ranking/aggregation techniques, and analytical reasoning for identifying problematic advertisers.
Data Manipulation (SQL/Python)Technical Screen - TikTokHardSoftware EngineerSchedule Seller Tasks with Tier-Weighted Round Robin
Design a task scheduler that dispenses seller tasks using tier-weighted round-robin across sellers while strictly preserving per-seller priority and FIFO order.
Coding & AlgorithmsOnsiteQueueHeapDesign - TikTokMediumData ScientistSelect max-discount product per category
This question evaluates proficiency in data manipulation and SQL querying—specifically use of window functions versus set-based alternatives, group-level ranking and tie-breaking, NULL-aware expressions, and numeric precision when computing discounts within the Data Manipulation (SQL/Python) domain.
Data Manipulation (SQL/Python)Online Assessment
TikTok