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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
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- 546
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- 11
- Topics
- 8
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Showing 1111–1140 of 4616 results
- Chicago Trading CompanyMediumSoftware EngineerImplement a Unique Pointer and Vector
This problem tests your understanding of C++ RAII, move semantics, template metaprogramming, and manual memory management by requiring the implementation of a scoped unique-ownership pointer and a custom dynamic array container.
Software Engineering FundamentalsTechnical ScreenC++RAIIMemory Management - ChimeMediumData ScientistAnalyze Acquisition Channels for User Value and Retention
This question evaluates proficiency in SQL/Python data manipulation and analytics, testing aggregation, cohort and retention analysis, ranking, joins and window-function usage along with interpretation of user-level revenue metrics.
Data Manipulation (SQL/Python)Technical Screen - ChimeMediumData ScientistDecide launch with CPA-profit trade-offs by segment
This question evaluates competency in metric-driven profit analysis, customer economics (LTV/CAC), segmentation effects, and interpretation of A/B experiment results.
Analytics & ExperimentationTechnical Screen - ChimeMediumData ScientistDefine and Analyze Early Engagement
Define an early user activation metric for a fintech platform, write a SQL query to measure monthly cohort activation rates across acquisition channels, and account for lifecycle maturity bias.
Data Manipulation (SQL/Python)Technical Screensqlcohort-analysisfintech - ChimeMediumProduct ManagerDescribe a 0-to-1 project you led
Prepare a Chime PM behavioral answer about leading a 0-to-1 product or growth initiative. The solution uses STAR structure, customer discovery, stakeholder alignment, MVP tradeoffs, fintech guardrails, launch metrics, and lessons learned.
Behavioral & LeadershipTechnical Screen - ChimeMediumData ScientistDesign an A/B launch amid marketing confounds
This question evaluates a candidate's competency in experimental design, causal inference, metric definition, statistical diagnostics, and decision-making under data-quality and marketing confounds within the Analytics & Experimentation domain.
Analytics & ExperimentationTechnical Screen - ChimeMediumBackend EngineerDesign browser history across tabs
This question tests the ability to design an efficient data structure for navigating browser history, requiring careful management of back/forward states across multiple independent tabs.
Software Engineering FundamentalsTechnical ScreenData StructuresStacksHash Maps - ChimeEasySoftware EngineerDesign load balancing, caching, and idempotent APIs
This question evaluates a candidate's competency in designing scalable, reliable backend architectures, specifically focusing on load balancing strategies, multi-layer caching, and idempotent API design.
System DesignTechnical Screen - ChimeMediumData ScientistDetermine Key Metrics for Spend-Tracker Launch Decision
Determine Key Metrics for Spend-Tracker Launch Decision evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationTechnical Screen - ChimeEasySoftware EngineerExplain sync/async, Go concurrency, SQL vs NoSQL
This question evaluates understanding of execution models (synchronous vs asynchronous and blocking vs non-blocking), Go concurrency patterns (goroutines, channels versus shared-memory with locks), and database paradigms (SQL vs NoSQL) relevant to backend engineering.
Software Engineering FundamentalsTechnical Screen - ChimeMediumProduct ManagerHow do you validate the problem and define V1?
Explain how a PM validates the right customer problem and defines V1 or MVP scope. The solution covers discovery, funnel data, problem statements, must-have journeys, stakeholder alignment, tradeoffs, compliance guardrails, launch metrics, and iteration decisions.
Product Design & StrategyTechnical Screen - ChimeMediumSoftware EngineerImplement single-tab browser history navigation
This question evaluates understanding of data structures, stateful API behavior, amortized time complexity, set membership tracking, and edge-case handling for implementing browser-like history navigation in the coding & algorithms domain.
Coding & AlgorithmsTechnical Screen - ChimeMediumData ScientistNavigate Complex Product Challenges in Behavioral Interviews
This interview question evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer for Navigate Complex Product Challenges in Behavioral Interviews states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Behavioral & LeadershipTechnical Screen - ChimeMediumData ScientistPropose Innovative Ideas and Convince Others Effectively
This interview question evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer for Propose Innovative Ideas and Convince Others Effectively states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Behavioral & LeadershipTechnical Screen - ChimeMediumBackend EngineerSolve classic backend coding problems
This problem tests your ability to handle string manipulation, recursion with backtracking, and mapping logic by generating all valid word combinations from a numeric keypad sequence.
Coding & AlgorithmsTechnical ScreenBacktrackingRecursionStrings - ChimeMediumData ScientistWrite SQL for noisy A/B launch metrics
This question evaluates SQL-based data manipulation and experimental analytics skills, including attribution of earliest exposures, censoring crossovers, session-based bot qualification, time-windowed conversion and revenue calculations, and exclusion of outage periods in PostgreSQL.
Data Manipulation (SQL/Python)Technical Screen - ChimeMediumData ScientistWrite rolling-window SQL over weekly cohorts
This question evaluates proficiency with SQL window functions and CTEs for time-based cohort aggregation, including rolling ROWS-based sums, LAG-based week-over-week percent change, DENSE_RANK ranking, and handling first- and second-purchase calculations.
Data Manipulation (SQL/Python)Technical Screen - CircleHardSoftware EngineerImplement Recipe Storage CRUD
This question evaluates the ability to design and implement in-memory data structures and APIs for CRUD operations, covering skills such as ID generation and parsing, string handling for case-insensitive uniqueness constraints, data modeling, and preserving original value casing.
Coding & AlgorithmsTechnical Screen - CircleMediumSoftware EngineerIn-Memory Bank System With Top-N Activity Ranking and Expiring Pending Transfers
Implement an in-memory banking class in stages: create accounts, deposit and pay, rank the top n accounts by transaction activity, and support transfers that hold funds until the recipient accepts within a time window or they are refunded. Tests state modeling, validation, and timestamp-driven expiry.
Software Engineering FundamentalsTechnical Screen - CiscoHardSoftware EngineerFormalize a Minimum-Trip Transport Puzzle with Horses and Ladders
Model a horses-and-ladders transport puzzle by clarifying legal moves, tracking resource state, and proving a minimum-trip plan is optimal.
Statistics & MathTechnical Screen - CiscoHardSoftware EngineerImplement an LFU Cache
This problem tests your ability to design a data structure that supports O(1) insertions and lookups while managing cache eviction based on access frequency and recency.
Coding & AlgorithmsTechnical ScreenHash TableLinked ListDesign - CiscoEasySoftware EngineerLongest Substring Without Repeated Characters
This problem tests string manipulation, hash map usage, and the sliding window technique to find a specific substring based on unique character constraints.
Coding & AlgorithmsTechnical ScreenSliding WindowStringsHash Map - CiscoEasySoftware EngineerReason About C Pointer and Array Declarations
This question tests the ability to parse complex C declarations and understand memory layout, pointer arithmetic, and the differences between pointers and arrays.
Software Engineering FundamentalsTechnical ScreenCPointersMemory - CitadelMediumData ScientistAnalyze Correlations and Generate Gaussians
This question evaluates understanding of correlation properties, feasible dependence constraints in multivariate distributions, construction of joint random variables with specified pairwise correlations, and methods for generating Gaussian samples from uniform random number generators, testing skills in probability, statistics, and simulation within the Machine Learning domain. It is commonly asked to assess both conceptual understanding of dependence structures and positive semidefiniteness and practical application of random variate generation techniques, reflecting a mix of conceptual and applied competencies for data scientist roles.
Machine LearningTechnical Screen - CitadelMediumData ScientistAnalyze Town Temperatures and Select Predictors for NYC
Implement exact pandas and NumPy functions for temperature statistics, single- and two-town regressions, deterministic return values, and greedy five-feature forward selection.
Machine LearningTechnical Screen - CitadelEasyFrontend EngineerBuild a Real-Time Event Feed Dashboard
Implement a robust React hook to manage a high-frequency, real-time event feed dashboard with pause/resume controls, out-of-order de-duplication, memory bounding, and rolling time-window statistics.
Software Engineering FundamentalsTechnical Screenreacttypescriptsliding-window - CitadelMediumData ScientistCalculate Probability of Third Card Being an Ace
Evaluates conditional probability with cards drawn without replacement after observing at least one Ace. Strong answers define the conditioning event, account for the number of Aces among the first two cards, and compute the probability that the third card is an Ace as 49/825.
Statistics & MathTechnical Screen - CitadelMediumSoftware EngineerChoose 200 of a Million Records to Label, Improving on Uniform Random Sampling
Tests the ability to define data informativeness under extreme budget constraints (selecting 200 out of 1,000,000 records) and design a scalable, one-shot sampling strategy that outperforms uniform random sampling in coverage and diversity.
Statistics & MathTechnical ScreenActive LearningSamplingClustering - CitadelEasyData ScientistChoose Between Precision and Recall for a Classification Decision
Review precision and recall for imbalanced classification and learn how both change with the decision threshold. Choose an operating point from error costs, capacity, calibration, uncertainty, and segment performance instead of treating either metric as universally best.
Machine LearningTechnical Screen - CitadelHardData ScientistClassify Variable-Length, Unordered Point Sequences with Missing Features
A staged live-coding ML task: classify whole sequences of 6-feature points as 0 or 1, then adapt the model as lengths vary from 16 to 100, point order stops being meaningful, and some features go missing. Tests model selection, length and permutation invariance, and practical missing-value handling.
Machine LearningTechnical Screen
Chime
Circle
Citadel