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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.
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Showing 2311–2340 of 4616 results
- MetaHardData ScientistBrainstorm how to optimize email engagement
This question evaluates a data scientist's competency in lifecycle email optimization, attribution of incremental on-site engagement, experiment design, metric selection, and trade-offs involving deliverability and guardrails within the Analytics & Experimentation domain.
Analytics & ExperimentationTechnical Screen - MetaMediumMachine Learning EngineerBuild Friend Recommendations
This problem tests your ability to manipulate graph-like data structures to perform neighbor analysis and efficient set operations to rank potential connections.
Coding & AlgorithmsTechnical ScreenGraphsHash MapsSocial Network Analysis - MetaMediumData ScientistCalculate CTR and ad revenue
This problem tests your ability to clean and join datasets, handle currency conversion, and aggregate metrics at different granularities.
Data Manipulation (SQL/Python)Technical ScreenSQLData AggregationMetrics - MetaMediumData ScientistCalculate Daily Survey Response Rates by Country
Write a PostgreSQL query to compute daily survey response rates at the country level using distinct user counts while handling orphan response logs and edge cases.
Data Manipulation (SQL/Python)Technical ScreenSQLPostgreSQLData Aggregation - MetaMediumData ScientistCalculate French User Engagement and U.S. Call Duration
This question evaluates proficiency in SQL-based data manipulation and analytics, testing skills such as joining event and profile tables, aggregating metrics, and computing user-level engagement proportions and average durations.
Data Manipulation (SQL/Python)Technical Screen - MetaMediumData ScientistCalculate Survey Response Rate and Quality Metric in SQL
This question evaluates SQL data-manipulation competencies such as aggregation, NULL handling, deduplication (first-per-group), and computing engagement and quality metrics from event logs.
Data Manipulation (SQL/Python)Technical Screen - MetaMediumData ScientistCalculate Video Call Usage Metrics by Country and Date
This question evaluates data manipulation and product-analytics skills, focusing on joining user and call datasets, aggregations for distinct-user percentages, and per-DAU duration calculations.
Data Manipulation (SQL/Python)Technical Screen - MetaEasySoftware EngineerCheck Whether a Letters-and-Numbers Abbreviation Matches a Word
Decide whether an abbreviation made of lowercase letters and decimal skip counts matches a given word, where each number skips that many characters and any number with a leading zero is invalid. It tests careful string scanning, multi-digit number parsing and end-of-input boundary checks.
Coding & AlgorithmsTechnical Screen - MetaMediumMachine Learning EngineerCheck diagonal and compute window statistics
This question evaluates understanding of array and matrix manipulation, sliding-window and streaming statistics, and appropriate data-structure choices for maintaining aggregates and order-statistics such as moving averages and sliding-window medians.
Coding & AlgorithmsTechnical Screen - MetaMediumMachine Learning EngineerCheck diagonal equality in a matrix
This question evaluates skill in matrix manipulation and algorithmic reasoning, specifically understanding diagonal traversal, equality checks, and handling boundary conditions such as empty matrices, single-row or single-column inputs, and negative values.
Coding & AlgorithmsTechnical Screen - MetaHardData ScientistChoose group-call size cap via experiment
This question evaluates a candidate's competency in experimental design, A/B testing and statistical analysis for product decisions, specifically testing metric selection, reliability and latency guardrails, stratified randomization, interference and clustering effects, heterogeneity detection, and operational stopping rules.
Analytics & ExperimentationTechnical Screen - MetaHardData ScientistClarify scope and align to mission
This question evaluates a data scientist's product sense, leadership and stakeholder-alignment skills, including scope clarification, mission translation, metric definition, and collaborative communication.
Behavioral & LeadershipTechnical Screen - MetaMediumSoftware EngineerClone list with random pointers
Meta software-engineer technical-screen coding question: deep-copy a singly linked list whose nodes carry an arbitrary random pointer (which may be null, point backward, or form cycles). It tests both the O(n)-space hash-map solution and the O(1)-auxiliary-space in-place weaving technique, plus reasoning about pointer integrity, cycle safety, and verifying the copy is structurally equal to and isolated from the original.
Coding & AlgorithmsTechnical Screen - MetaHardData ScientistCommunicate trade-offs and influence launch
This question evaluates product judgment, experimentation interpretation, and cross-functional leadership skills for a data scientist, focusing on communicating trade-offs between per-account metric lifts and cross-account cannibalization; Category: Behavioral & Leadership, Domain: data science and product experimentation.
Behavioral & LeadershipTechnical Screen - MetaMediumData ScientistCompare Survey Satisfaction for New and Established Users
Tests your ability to write PostgreSQL queries that segment users into cohorts based on date logic, filter invalid survey events, and calculate aggregate satisfaction metrics.
Data Manipulation (SQL/Python)Technical Screensqlpostgresqldata-aggregation - MetaMediumData ScientistCompute 7-day views and reactions by relationship
This question evaluates skills in SQL-based data manipulation—specifically deduplication by longest duration, join-based attribution of reactions to views, window functions, distinct counts, aggregations, and date-range filtering within the Data Manipulation (SQL/Python) domain.
Data Manipulation (SQL/Python)Technical Screen - MetaMediumData ScientistCompute CTR overall and by campaign type
This question evaluates data manipulation and analytics skills, specifically SQL aggregations, deduplication of event logs, time-window filtering, joins to campaign metadata, and safe ratio computation including division-by-zero handling.
Data Manipulation (SQL/Python)Technical Screen - MetaMediumSoftware EngineerCompute Exclusive Execution Times
This problem tests your ability to manage state in nested processes using a stack data structure to track the exclusive execution time of functions based on a log of start and end events.
Coding & AlgorithmsTechnical ScreenStackString ParsingSimulation - MetaHardData ScientistCompute High-Call Usage Rates
This question evaluates a candidate's ability to perform advanced data manipulation and analytical SQL tasks, including joins, aggregations, timezone-aware date handling, rolling window metrics, distinct user counting, and counting user participations across roles.
Data Manipulation (SQL/Python)Technical Screen - MetaHardData EngineerCompute Max Score From Up to 3 Categories
This Coding & Algorithms question in the Data Engineer domain evaluates grouping and top‑k aggregation concepts, testing the ability to combine per-category aggregation with selection under a uniqueness constraint.
Coding & AlgorithmsTechnical Screen - MetaEasySoftware EngineerCompute Range Sum Quickly
This question tests the ability to trade preprocessing time for query performance using prefix sum arrays to efficiently calculate the sum of elements within a specified range.
Coding & AlgorithmsTechnical ScreenPrefix SumArraysOptimization - MetaMediumData ScientistCompute SHOP spend share and model performance
This question evaluates proficiency in SQL/Python data manipulation and analytics, focusing on aggregations, joins, time-window computations, handling missing or zero values, and deriving key metrics such as revenue share and revenue-per-conversion.
Data Manipulation (SQL/Python)Technical Screen - MetaEasySoftware EngineerCompute Sliding Window Averages
This question tests the ability to implement a sliding window algorithm to compute the average of contiguous subarrays, emphasizing optimization of time complexity.
Coding & AlgorithmsTechnical ScreenSliding WindowArraysOptimization - MetaMediumData ScientistCompute ad revenue metrics by geography in SQL
In the Data Manipulation (SQL/Python) domain, this intermediate-level question evaluates SQL aggregation, join logic between impressions and clicks, date-based UTC attribution, user-geo joins, and null/divide-by-zero-safe computation of derived metrics (CTR, RPM) at the country-day granularity.
Data Manipulation (SQL/Python)Technical Screen - MetaMediumData ScientistCompute and correct correlation significance inflation
This question tests the understanding of how multiple hypothesis testing increases the risk of false positives (Type I error) in high-dimensional correlation matrices and requires the application of correction methods to maintain statistical integrity.
Statistics & MathTechnical ScreenStatisticsHypothesis TestingCorrelation - MetaMediumSoftware EngineerCompute binary tree diameter
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Compute binary tree diameter states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - MetaMediumData ScientistCompute binary-tree diameter via return-only DFS
This question evaluates algorithmic problem-solving with binary trees, focusing on tree traversal techniques, recursion versus iterative implementations, and analysis of time and space complexity including worst-case input shapes such as skewed trees.
Coding & AlgorithmsTechnical Screen - MetaMediumData EngineerCompute capacities after site closures
This question evaluates a candidate's ability to manipulate nested dictionary data structures and perform aggregate capacity computations, assessing data transformation, mapping, and set-based reasoning skills relevant to a Data Engineer within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - MetaMediumData ScientistCompute cohort GMV and payer rate with edge cases
This question evaluates a data scientist's competency in cohort-based GMV calculation, payer-rate measurement, and handling common edge cases across events, orders, payments, and refunds.
Data Manipulation (SQL/Python)Technical Screen - MetaMediumSoftware EngineerCompute interval mode, BST range sum, exclusive time
This multipart question evaluates proficiency in interval coverage and frequency analysis, binary search tree range-sum queries with preprocessing for repeated queries, and exclusive-time computation from call logs, covering concepts such as event counting/sweep-line, BST traversal and augmentation, and nested-call time accounting.
Coding & AlgorithmsTechnical Screen
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