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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 27 of 80
Coding questions · Snapchat
Design Manhattan-distance meeting point finder
This question evaluates algorithmic problem-solving and data-structure design skills for geometric aggregation problems, focusing on properties of Manhattan distance, handling dynamic updates, and analyzing time/space complexity within the Coding & Algorithms domain.
Coding questions · Stripe
Design metrics and write SQL for a case
This question evaluates the ability to define time‑bounded, attributable conversion metrics and to implement joins, aggregations, and diagnostic checks in SQL to measure marketing outreach impact.
Coding questions · Airbnb
Design mutable sum-tree with fast queries
This question evaluates proficiency in designing dynamic data structures for mutable rooted trees, including maintenance of subtree sums, parent/child link management, and analysis of update and query complexities within the Coding & Algorithms domain; it emphasizes practical application of algorithmic design coupled with conceptual understanding of invariants and amortized complexity. It is commonly asked in technical interviews because it probes reasoning about correctness and performance under mutations, handling edge cases such as subtree deletion and reattachment, and the ability to specify algorithmic approaches and complexity guarantees rather than implementation details.
Coding questions · xAI
Design O(1) random-sampling set
This question evaluates a candidate's competency in data-structure design, randomized algorithms, and algorithmic complexity analysis within the Coding & Algorithms domain, with a focus on achieving expected O(1) operations for insert, remove, and uniform sampling.
Coding questions · Salesforce
Design O(nm) grouping of rearranged strings
This question evaluates a candidate's understanding of string manipulation, hashing and frequency-count techniques, algorithmic optimization, and time/space complexity analysis when grouping anagrams.
Coding questions · Coinbase
Design order stream with state transitions
Design order stream with state transitions 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 questions · Patreon
Design org chart lookup with preprocessing
This question evaluates skills in data structures and algorithms, specifically tree/forest representation, aggregation of subtree metrics, dynamic updates, and rigorous time and space complexity analysis.
Coding questions · Circle
Design payment scheduler with cancel and top-K outgoing
This question evaluates knowledge of designing stateful in-memory services, efficient data structures and algorithms for scheduled task execution and top‑K outgoing aggregation, and correctness in handling cancellation, failure semantics, and related edge cases.
Coding questions · Stripe
Design payment-to-invoice matcher with priorities
This question evaluates parsing and data modeling skills, deterministic matching algorithms with prioritization and tie-breaking, handling monetary values as integer cents, and the ability to design comprehensive test suites for edge cases.
Coding questions · Meta
Design prefix-sum function and max stack
This question evaluates understanding of prefix-sum precomputation for constant-time range queries and the design of a max-enabled stack, focusing on data structure design, algorithmic complexity, and space-time trade-offs.
Coding questions · Airbnb
Design refundable transaction ledger and prioritization rules
This question evaluates knowledge of data structures and algorithms for transactional ledgers, including tracking payments and refundable balances, rule-based prioritization for allocating refunds, handling partial and multiple refunds, and ensuring correctness when payments and refunds interleave.
Coding questions · Roblox
Design robot path boundedness with repeats
This question evaluates algorithmic skills in parsing compressed instruction strings, finite-state simulation, and spatial reasoning to determine path boundedness, and it belongs to the Coding & Algorithms domain.
Coding questions · Uber
Design room progression with leaderboard
This question evaluates the ability to design efficient dynamic data structures and algorithms for maintaining per-player state and a real-time leaderboard, including score aggregation, room transitions, and high-throughput updates.
Coding questions · OpenAI
Design Schema and Logic for Subscription Event Tracking
This question evaluates proficiency in event-driven data modeling, temporal state derivation, and implementation of SQL/Python logic to compute per-user subscription status and history within the Data Manipulation (SQL/Python) domain.
Coding questions · Freddie Mac
Design SQL cleaning, mapping, dedupe, and keying
This question evaluates proficiency in data cleaning and normalization, deduplication, timestamp parsing, simple email validation, country code standardization, source-to-target mapping, and DDL/DML design using SQL (and optionally Python).
Coding questions · Amazon
Design SQL/Pandas aggregations on retail schema
This question evaluates ability to perform time-based aggregations and data manipulation using SQL and pandas, including per-order revenue calculation, same-day de-duplication, rolling-window sums, and intra-customer ranking.
Coding questions · Meta
Design SQL Query for Shop Visibility and User Activity Metrics
This question evaluates proficiency in SQL-based data manipulation—aggregation, JOINs, CASE expressions, window functions, ranking, and metric design for user tenure segmentation and temporal activity comparisons.
Coding questions · Vanta
Design streaming test logger and queries
This question evaluates a candidate's ability to design streaming data structures and time-series algorithms to track state transitions and compute interval queries, covering competencies in online/event-processing algorithms, interval overlap aggregation, and algorithmic complexity analysis within the Coding & Algorithms domain.
Coding questions · Oracle
Design structure for first unique login user
This question evaluates a candidate's ability to design an efficient online data structure that maintains a stream of login events and supports constant-time updates and queries for the earliest user with exactly one login.
Coding questions · Amazon
Design student–course data models and SQL
This question evaluates data modeling, database design, and SQL proficiency—covering normalization, schema constraints, indexing, star-schema warehousing, slowly changing dimensions, partitioning strategies, and complex analytic queries—in the domain of relational databases and data warehousing (Data Manipulation/SQL).
Coding questions · Vanta
Design test logging and failure-window queries
This question evaluates streaming data structures, time-series event processing, interval/temporal query algorithms, and complexity analysis as applied to a software engineer role.
Coding questions · Vanta
Design test-run logging and query functions
This question evaluates proficiency in time-series logging, event-driven state transitions, interval and sliding-window algorithms, and efficient data-structure design for streaming updates.
Coding questions · Databricks
Design Tic-Tac-Toe and QPS data structures
This question evaluates data-structure and API design skills, covering state management and efficient update/query algorithms for a generalized Tic-Tac-Toe with uniform-random move selection, as well as time-series aggregation and streaming-log techniques for computing QPS from non-decreasing timestamps.
Coding questions · Uber
Design time-versioned KV without timestamp argument
This question evaluates understanding of time-versioned key-value stores, monotonic timestamp assignment, clock skew handling, concurrent writes, appropriate data structures, and time/space complexity analysis.