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Coding questions
Explore algorithm tutorials, coding and system design questions, interview experiences, and computer science study guides.
1,899 resources · Page 12 of 80
Coding questions · Meta
Compute cumulative metrics with full joins
This question evaluates proficiency in SQL data manipulation and data engineering competencies, focusing on merging per-day and cumulative metrics, join semantics, and null-value handling in the Data Manipulation (SQL/Python) domain.
Coding questions · Uber
Compute currency conversion via graph search
This question evaluates graph modeling and pathfinding with weighted edges, numerical reasoning about multiplicative rates and floating-point precision, and the ability to analyze algorithmic time and space complexity.
Coding questions · Capital One
Compute Customer Spend and Engineer Features for 2023
This question evaluates proficiency in SQL-based temporal aggregation and Python feature engineering on transactional datasets, including computing monthly spend summaries and engineering category-level spending features.
Coding questions · Tubi
Compute daily net users from event logs
This question evaluates SQL-based data manipulation skills focused on daily aggregation, cohort and retention calculations, deduplicating event records, and grouping metrics by device_platform.
Coding questions · Meta
Compute daily post success rate for last 7 days
This question evaluates data manipulation and analytical competencies in Data Manipulation (SQL/Python), focusing on time-windowed aggregations, rate calculations, handling nulls/zero denominators, numeric type and rounding considerations, and producing per-calendar-date outputs.
Coding questions · Meta
Compute Daily Revenue by Creation Source
This question evaluates proficiency in data manipulation and analytical SQL/Python skills, including aggregation, date truncation, joins, window functions, and period-over-period comparisons for revenue metrics.
Coding questions · Amazon
Compute daily work hours from in/out events
This question evaluates a candidate's ability to manipulate time-series punch-event data, including temporal pairing of in/out events, splitting shifts across calendar days, rounding and aggregating hours, and detecting data-quality issues such as overlaps or orphaned events using SQL or Python.
Coding questions · DoorDash
Compute dasher pay from deliveries
This question evaluates competency in data manipulation, schema design and validation, time-based aggregation, pay-computation logic, and handling of edge cases using SQL or Python.
Coding questions · xAI
Compute dasher pay from order events
This question evaluates a candidate's ability to process time-based event streams, manage overlapping active intervals, and compute aggregate payouts under concurrency constraints.
Coding questions · DoorDash
Compute dasher payout from API data
This question evaluates a candidate's proficiency in data manipulation and transaction aggregation using SQL or Python, encompassing time-zone-aware timestamp handling, pagination, late or missing events, cancellations and negative adjustments, rounding rules, and itemized breakdowns.
Coding questions · Glean
Compute DAU and rolling MAU with zero days
This question evaluates a data scientist's proficiency in time-series analytics and data aggregation, focusing on computing daily active users and a 30-day rolling MAU from user and login tables, and falls under the Data Manipulation (SQL/Python) domain.
Coding questions · Sonatus
Compute days until a higher reading
This question evaluates proficiency in array processing and the next-greater-element concept, measuring algorithmic reasoning about sequence traversal, comparisons, and managing time/space trade-offs.
Coding questions · Amazon
Compute delay times in priority array
This question evaluates algorithmic efficiency in array processing, specifically reasoning about nearest-smaller relationships and the use of auxiliary structures to achieve subquadratic performance.
Coding questions · DoorDash
Compute delivery times on a grid
This question evaluates understanding of graph traversal and shortest-path algorithms, grid-based pathfinding, and data structure selection for representing sparse or large grids within the Coding & Algorithms domain.
Coding questions · Instacart
Compute delivery wait times
This question evaluates competence in event-driven simulation, scheduling and queueing concepts, and algorithmic analysis by requiring computation of average customer waiting time for single and multiple shoppers.
Coding questions · DoorDash
Compute Differences Between Catalog Trees
This question evaluates proficiency in tree algorithms and hierarchical data comparison, including simultaneous traversal, subtree sizing, key-based node identity, and time/space complexity reasoning, and is commonly asked to assess algorithmic problem-solving and trade-off analysis when comparing structured datasets.
Coding questions · Visa
Compute distinct sums from limited coins
This question evaluates algorithmic problem-solving skills in combinatorics and resource-constrained subset-sum computation, focusing on dynamic programming, optimization, and complexity analysis within the Coding & Algorithms domain.
Coding questions · LinkedIn
Compute each member’s current notification status
A LinkedIn data scientist SQL screen: given an end-of-January notification-status snapshot and a February log of turn_on/turn_off actions, compute each member's current status as of 2020-02-29, keeping members from either table. Follow-ups explore reconstructing state when the action log has no date column — unsolvable in general, but recoverable via action-count parity when every action is a guaranteed valid transition.
Coding questions · Netflix
Compute Earliest Completion Times
This question evaluates understanding of directed acyclic graphs, dependency resolution, computation of earliest task completion times, and cycle detection within prerequisite relationships.
Coding questions · Chime
Compute early signals for user retention
This question evaluates the ability to compute cohort-based early engagement metrics and Day-30 retention using time-windowed joins, aggregation, bucketing, and handling edge cases such as users with zero or pre-signup transactions.
Coding questions · Meta
Compute Effective Reads with SQL and Python Streaming
This question evaluates proficiency in event-level data aggregation, sessionization, windowing, and stateful stream processing across SQL and Python, including computing aggregated metrics such as total watch duration and peak screen coverage.
Coding questions · Uber
Compute ETA shift and conversion uplift
This question evaluates proficiency in SQL and Python for time‑series data manipulation and experimental analysis, covering window functions (7‑day percentile_cont medians), date spines and timezone‑aware timestamp truncation, conversion-rate aggregation, difference‑in‑differences uplift estimation, and CUPED adjustment with cluster‑robust standard errors. It is commonly asked to assess practical data engineering and applied statistics skills in the Data Manipulation (SQL/Python) domain, testing applied implementation and causal inference ability rather than only conceptual understanding.
Coding questions · Anthropic
Compute Exclusive Time from Stack Events
Compute aggregate exclusive execution time for each function from nested start and end events, including recursive calls. Use a stack over a validated single-threaded trace, apply half-open time intervals, and return deterministic sorted results.
Coding questions · Uber
Compute final prices with next smaller discount
This question evaluates array-processing and algorithmic problem-solving skills, focusing on reasoning about subsequent elements to compute element-wise discounts under input constraints.