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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
- Companies
- 11
- Topics
- 8
- Languages
Showing 1–30 of 781 results
- AbridgeHardSoftware EngineerExpand a Nested Repeat-Count Encoded String
From an Abridge online assessment: decode a string in which k[text] means the bracketed text repeated k times, with multi-digit counts, nested brackets and plain letters between encoded parts. It tests parsing nested structure correctly and building the expanded output efficiently.
Coding & AlgorithmsOnline Assessment - AbridgeHardSoftware EngineerRun-Length Compress a Character List With Multi-Digit Counts
From an Abridge online assessment: run-length compress a list of characters, writing each run of equal adjacent characters as the character followed by its length, with lengths of 10 or more split into separate digit characters. It tests careful run handling and the in-place, constant-space form of the problem.
Coding & AlgorithmsOnline Assessment - AbridgeHardSoftware EngineerSum of Integers Up to n Divisible by 3, 5, or 7
From an Abridge online assessment: given a positive integer n, return the sum of all integers from 1 to n that are divisible by 3, 5 or 7, adding numbers such as 15 or 21 only once. It tests precise handling of overlapping divisibility conditions and inclusive range boundaries.
Coding & AlgorithmsOnline Assessment - AdobeMediumSoftware EngineerFind Top-Funded Villages and Their Top Projects
Tests the ability to write a multi-level SQL aggregation with window functions, exact date filtering, tie handling, and deterministic sorting.
Data Manipulation (SQL/Python)Online Assessmentsqlwindow-functionsaggregation - AirbnbMediumSoftware EngineerBuild an Incremental Loyalty-Points Ledger with Scheduled, Cancelable Transfers
Implement an in-memory loyalty-points ledger that grows in three stages: atomic transfers between accounts, transfers scheduled for a future point on a simulated clock, and cancellation of a transfer before it fires. Tests incremental state-machine design, validating before mutating, and keeping point totals correct across every sequence of calls.
Software Engineering FundamentalsOnline Assessmentstate-machineoopsimulation - AirbnbMediumSoftware EngineerDefine a File Store with User Quotas and Compression
Implement an in-memory cloud file store that supports file creation, copying, prefix/suffix search, per-user storage quotas, and atomic file compression/expansion.
Software Engineering FundamentalsOnline AssessmentData StructuresDesignString - AirbnbMediumSoftware EngineerDesign a Multi-Level In-Memory Cloud Storage Service
Design a multi-tiered in-memory cloud storage system supporting staged uploads, capacity limits, prefix search ranking, and conflict-aware backup and restore operations.
Software Engineering FundamentalsOnline AssessmentDesignData StructuresHash Table - AirbnbMediumSoftware EngineerDesign a Stateful Banking System with Scheduled Payments and Account Merges
Design an in-memory stateful banking system that supports account creation, transfers, spending leaderboards, scheduled payments with deterministic backlog processing, and account merges.
Software Engineering FundamentalsOnline Assessmentdata-structuresheapsystem-simulation - AirbnbHardSoftware EngineerDesign a Stateful Working Hours Register
Design an in-memory working hours and compensation tracking register that supports badge events, top-k leaderboards, scheduled rate changes, and interval-based historical earnings calculations.
Software Engineering FundamentalsOnline AssessmentDesignIntervalsBinary Search - AirbnbEasySoftware EngineerDesign an In-Memory Cloud Storage Service with Users, Backups, and Restore
Implement an in-memory cloud storage system supporting user storage limits, globally unique files, ranked file queries, account merges, and transactional backup and restore operations.
Software Engineering FundamentalsOnline AssessmentObject-Oriented DesignData StructuresHash Table - AirbnbMediumSoftware EngineerImplement Connect Four with win detection
This question evaluates a candidate's ability to design efficient data structures and algorithms for real-time game state management, including win detection, API design, time/space complexity analysis, and handling edge cases such as full or out-of-range columns.
Coding & AlgorithmsOnline Assessment - AirbnbMediumSoftware EngineerImplement a Multi-Level Recipe Management Service
Design and implement an in-memory recipe management service supporting deterministic querying, defensive data isolation, atomic updates, and secondary index maintenance.
Software Engineering FundamentalsOnline AssessmentData StructuresAPI DesignInverted Index - AirbnbHardSoftware EngineerImplement a Time-Aware Banking System
Design and implement a stateful, time-aware in-memory banking ledger that handles atomic transfers, deferred/scheduled executions, account mergers, historical balance queries, and activity rankings.
Software Engineering FundamentalsOnline AssessmentDesignHeapBinary Search - AirbnbMediumSoftware EngineerImplement a Time-Aware Task Management System
Design and implement an in-memory, time-aware task management class that supports scheduling, rescheduling, canceling, and prioritized polling based on timestamps and priorities.
Software Engineering FundamentalsOnline AssessmentHeapHash TableSystem Design - AirbnbMediumSoftware EngineerIn-Memory Banking System with Immediate, Offline and Deletable Transfers
Implement an in-memory banking system across progressive levels: create users, move money immediately, accept offline transfers that take effect later, and delete transfers that have not completed. It tests state modeling, validation before mutation, conservation of money across every sequence of operations, and extensible class design.
Software Engineering FundamentalsOnline Assessment - AirbnbHardSoftware EngineerIn-Memory Banking System: Transfers, Top Spenders, Scheduled Payments, Account Merges
A four-level in-memory banking system: create accounts, deposit and transfer, rank top spenders by outgoing value, run scheduled payments that must execute in timestamp order before every later operation, and merge accounts while keeping both balances and histories. It tests incremental class design and time-ordered state.
Software Engineering FundamentalsOnline Assessment - AirbnbMediumSoftware EngineerIn-Memory Workspace Credit System With Transfers, Top-K and Scheduled Transfers
Implement an in-memory workspace credit system in levels: create workspaces, add credit and transfer it instantly, return the top K workspaces, then schedule and cancel future transfers that must take effect before each later operation. It tests clean state management, deterministic ordering, time-based processing and extensible code under a tight time limit.
Software Engineering FundamentalsOnline Assessment - AirbnbHardSoftware EngineerProcess a Timestamped Workspace Credit Ledger
Design and implement an in-memory timestamped credit ledger that supports deposits, transfers, spending with delayed cashback rewards, account merges, balance queries, and spend rankings.
Coding & AlgorithmsOnline AssessmentData StructuresDesignHeap - AirbnbMediumSoftware EngineerTask Management System: Priorities, Name Search, User Quotas and Expiring Assignments
A four-level coding assessment that builds an in-memory task management system: adding, updating and retrieving tasks, name search and priority listing, users with quotas and expiring time-based assignments, then task completion and overdue reporting. It tests extensible design, deterministic ordering and time handling.
Software Engineering FundamentalsOnline Assessment - AirbnbMediumSoftware EngineerTimestamped Parcel Attribute Store With Compare-and-Set, Prefix Listing and TTL
Implement a timestamped in-memory store of parcel attributes with overwriting set, get and a compare-and-set update, then list attributes as name(value) sorted by name with an optional prefix filter, and finally add per-attribute TTLs that hide expired values. It tests precise operation semantics, expiry rules and incremental class design.
Software Engineering FundamentalsOnline Assessment - AirbnbMediumSoftware EngineerWorkspace Credit Ledger: Transfers, Top-K, Scheduled Transfers, Merges, Balance History
A four-level coding assessment that builds an in-memory credit ledger for workspaces, much like bank accounts. Levels add deposits, instant transfers with a top-k ranking, scheduled transfers with cancellation, and account merges with historical balance lookups, testing stateful class design, time handling and edge cases.
Software Engineering FundamentalsOnline Assessment - Akuna CapitalMediumSoftware EngineerAnswer SQL MCQs with reasoning
This question evaluates proficiency in SQL query semantics and reasoning about relational operations—specifically INNER, LEFT, and RIGHT JOIN behavior; GROUP BY and HAVING usage; NULL handling in comparisons and aggregates; window functions such as ROW_NUMBER and RANK; and the logical query processing order—within the Data Manipulation (SQL/Python) domain. It is commonly asked to assess the ability to interpret and justify query outcomes versus alternative answers, testing both conceptual understanding of relational theory and practical application of SQL query behavior.
Data Manipulation (SQL/Python)Online Assessment - Akuna CapitalMediumData EngineerCompute Graph Spread and Portfolio Trades
This problem tests graph traversal (connected components) and hash-map manipulation to calculate net delta changes in portfolio assets within identified groups.
Coding & AlgorithmsOnline AssessmentGraphDFS/BFSHash Map - Akuna CapitalMediumSoftware EngineerCompute max profit across dated stock quotes
This question evaluates a candidate's ability to reason about time-series and transaction-constrained optimization, including handling unsorted inputs, duplicate records, and constructing an explicit sequence of trades under ordering and no-short-selling constraints.
Coding & AlgorithmsOnline Assessment - Akuna CapitalMediumSoftware EngineerCompute min operations to transform integers
This question evaluates algorithmic problem-solving skills related to integer transformations and reasoning about sequences of allowed operations, focusing on optimizing the number of steps. It is commonly used in the Coding & Algorithms domain to assess practical application of algorithmic thinking and time-complexity analysis, testing efficiency reasoning rather than purely conceptual knowledge.
Coding & AlgorithmsOnline Assessment - Akuna CapitalEasySoftware EngineerDesign user communication functions
This interview question evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer for Design user communication functions states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignOnline Assessment - Akuna CapitalMediumSoftware EngineerEvaluate SQL expressions for zero
This question evaluates understanding of SQL type coercion, boolean semantics, comparison operators, and dialect-specific evaluation behavior (for example, MySQL), focusing on interpreting expressions that may evaluate to zero.
Data Manipulation (SQL/Python)Online Assessment - Akuna CapitalHardData ScientistFind minimum swaps to sort array with duplicates
This question evaluates array manipulation and permutation-based reasoning for minimizing swap operations, including handling of duplicate values and performance considerations, within the Coding & Algorithms domain for a Data Scientist role.
Coding & AlgorithmsOnline Assessment - Akuna CapitalHardSoftware EngineerFix and harden an object pool
This interview question evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer for Fix and harden an object pool states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignOnline Assessment - Akuna CapitalMediumSoftware EngineerHeapify an array into a max-heap
This question evaluates understanding of heap data structures and the in-place bottom-up heapify algorithm for building a max-heap on a 0-indexed array, testing skills in array manipulation, heap invariants, and algorithmic reasoning.
Coding & AlgorithmsOnline Assessment
Abridge
Adobe
Airbnb
Akuna Capital