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Coding & Algorithms 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 2761–2790 of 3276 results

  • StripeHardSoftware Engineer
    Find Weekly Deployment Windows Across Time Zones

    Determine the first k non-overlapping deployment windows across a 3-week search horizon by mapping weekly recurring local allow and freeze rules into a repeating UTC timeline.

    Coding & AlgorithmsOnline AssessmentIntervalsPrefix SumSliding Window
  • StripeMediumSoftware Engineer
    Find deployable slots in a recurring week from allowed and freeze windows

    A coding exercise on a recurring 10,080-minute week: combine allowed and freeze deployment windows into deployable slots, then add per-window time-zone offsets, the current time, a lead time, a minimum slot length and a cap of k results. It tests interval merging and subtraction, wrap-around at the week boundary and careful edge-case handling.

    Coding & AlgorithmsOnsite
  • StripeMediumSoftware Engineer
    Find linked merchants by shared fields

    This question tests the ability to model entity relationships using a graph representation and implement a traversal algorithm to identify connected components based on shared identity fields.

    Coding & AlgorithmsTechnical ScreenGraphsHash MapsDisjoint Set Union
  • StripeMediumSoftware Engineer
    Find linked user records by similarity

    This question evaluates the ability to compute weighted field-based similarity and reason about adjacency relationships in an undirected graph, testing competencies in similarity scoring, record linkage, and basic graph traversal.

    Coding & AlgorithmsTechnical Screen
  • StripeMediumSoftware Engineer
    Find linked user records by weighted similarity

    This problem tests your ability to model relationships as a graph and compute connected components based on weighted similarity scores between user records.

    Coding & AlgorithmsTechnical ScreenGraphDSUOptimization
  • StripeHardSoftware Engineer
    Generate Available 30-Minute Time Slots

    This problem tests your ability to manipulate time intervals, handle recurring weekly schedules, and perform intersection logic between availability windows and existing booked appointments.

    Coding & AlgorithmsTechnical ScreenIntervalsDatetimeScheduling
  • StripeMediumSoftware Engineer
    How to find the cheapest flight within K stops

    This problem tests your ability to find the shortest path in a weighted graph under a specific constraint on the number of edges (stops).

    Coding & AlgorithmsTechnical ScreenGraphDynamic ProgrammingShortest Path
  • StripeMediumSoftware Engineer
    How to settle multi-person debts in minimum transactions

    Tests algorithm design and combinatorial search to settle multi-party debts with the minimum number of transfer transactions.

    Coding & AlgorithmsTechnical ScreenBacktrackingDynamic ProgrammingBitmask
  • StripeMediumSoftware Engineer
    Implement Billing Coding Exercises

    Implement a subscription proration and billing reconciliation engine that generates line items across plan changes and computes the outstanding balance against posted payments.

    Coding & AlgorithmsOnsitealgorithmsbillingreconciliation
  • StripeMediumSoftware Engineer
    Implement JSON parsing and HTTP integration tasks

    Tests practical software engineering skills in parsing JSON data, constructing batch HTTP requests, mapping returned attributes (such as color codes to coordinate points), and handling API errors.

    Coding & AlgorithmsTechnical ScreenAPI DesignJSONHTTP Client
  • StripeHardSoftware Engineer
    Implement Validation and String Compression

    This problem tests your ability to design a custom parser and recursive string processor that handles nested patterns while enforcing strict input validation.

    Coding & AlgorithmsOnsiteStringsStackRecursion
  • StripeMediumSoftware Engineer
    Implement a Datacenter Request Router

    This problem tests the ability to manage stateful datacenter metadata and implement a routing algorithm that prioritizes proximity (Haversine distance) while respecting capacity constraints.

    Coding & AlgorithmsOnline AssessmentGeometryHash MapSorting
  • StripeMediumSoftware Engineer
    Implement bitmap font render/compress/invert

    This problem tests your ability to manipulate 2D bit arrays, implement Run-Length Encoding (RLE) for data compression, and perform grid-based coordinate transformations.

    Coding & AlgorithmsOnline AssessmentArraysStringsCompression
  • StripeMediumSoftware Engineer
    Implement multi-network card validator with Luhn

    This question evaluates a candidate's ability to implement and reason about the Luhn checksum, multi-network payment card format validation, combinatorial completion for redacted digits, single-error correction models, and efficient search/pruning with deterministic duplicate avoidance.

    Coding & AlgorithmsOnline Assessment
  • StripeMediumSoftware Engineer
    Implement multi-part cost calculator

    This question evaluates a candidate's ability to implement robust data-processing and numeric computation logic for a multi-part cost calculator, covering input validation, per-item discounts and tax, sorting semantics, multi-currency conversion, and precise monetary rounding.

    Coding & AlgorithmsTechnical Screen
  • StripeEasySoftware Engineer
    Implement stateful connection router simulator

    This question evaluates design and implementation skills for a stateful connection router, focusing on round-robin load distribution, connection lifecycle handling (duplicate connects, disconnects, shutdowns), and per-target capacity and mapping management.

    Coding & AlgorithmsOnline Assessment
  • StripeMediumData Scientist
    Implement streaming per-user reservoir sampling

    This question evaluates a candidate's competency in streaming algorithms, per-user reservoir sampling, probabilistic reasoning and proof of correctness, concurrent/distributed merging, and engineering trade-offs for memory and amortized update efficiency.

    Coding & AlgorithmsTechnical Screen
  • StripeEasyData Scientist
    Match payments to invoices by memo or amount

    This question evaluates string parsing, record linkage, and algorithmic matching skills for data reconciliation tasks, including handling messy memo text, exact amount matches, and tie-breaking by earliest due date.

    Coding & AlgorithmsTechnical Screen
  • StripeMediumSoftware Engineer
    Match payments to invoices with fallback rules

    This problem tests the ability to implement a multi-pass matching algorithm that prioritizes exact identifier matches before applying fuzzy numeric heuristics.

    Coding & AlgorithmsTechnical ScreenHashMapsAlgorithmsData Structures
  • StripeMediumSoftware Engineer
    Minimize total factory cost with distance penalties

    This problem tests your ability to use dynamic programming to minimize a total cost function that incorporates both intrinsic production costs and location-based transition penalties.

    Coding & AlgorithmsTechnical ScreenDynamic ProgrammingOptimizationAlgorithms
  • StripeMediumSoftware Engineer
    Parse and Format Arbitrarily Nested Tasks from CSV

    Tests parsing RFC 4180-compliant CSV records containing hierarchical tasks and rendering an arbitrarily nested forest with proper tree line prefixes (`├── `, `└── `, and `│ `).

    Coding & AlgorithmsTechnical Screentreerecursionstring-parsing
  • StripeMediumSoftware Engineer
    Plan bicycle routes on a city map

    This question evaluates graph algorithms and pathfinding competencies, multi-criteria optimization and weighting, data structure selection, heuristic design, handling dynamic updates and closures, and correctness and edge-case reasoning for route planning.

    Coding & AlgorithmsTechnical Screen
  • StripeMediumSoftware Engineer
    Process Transactions and Compute Balances

    This problem tests your ability to manage stateful account data, handle time-ordered transaction processing, and implement basic validation logic for financial integrity.

    Coding & AlgorithmsTechnical ScreenSortingHash MapSimulation
  • StripeMediumSoftware Engineer
    Process auth requests with fraud rules

    This question evaluates a candidate's ability to implement stateful stream processing and event handling, including applying time-scoped fraud rules to authorization requests, maintaining chronological ordering, and producing verified outputs via unit tests.

    Coding & AlgorithmsTechnical Screen
  • StripeMediumSoftware Engineer
    Propagate runtime ID across API requests

    Implement a request interpolator that traverses nested request payloads and URLs to replace placeholder variables with runtime IDs while preserving native data types.

    Coding & AlgorithmsTechnical ScreenRecursionString ParsingJSON
  • StripeMediumSoftware Engineer
    Register Data Centers and Route to the Nearest Healthy Region

    Implement a stateful command processor to register data centers, update their operational health, and route incoming requests to the nearest healthy data center using the Haversine distance formula.

    Coding & AlgorithmsOnline AssessmentDesignGeometryParsing
  • StripeMediumSoftware Engineer
    Resolve user roles across account hierarchy

    This problem tests your ability to navigate hierarchical structures (a tree of accounts) and perform efficient permission aggregation using set operations.

    Coding & AlgorithmsTechnical ScreenGraphHash MapHierarchy
  • StripeHardSoftware Engineer
    Split-Tender Payment Events with Gift Card Expiry, ZIP Surcharges and Refunds

    Implement a payment event processor for split-tender retail purchases, where each charge spends a customer's gift cards before billing the rest to a credit card. It tests precise simulation: earliest-expiry card priority with lexicographic tie-breaks, ZIP-range surcharges on the credit card portion, refunds split between card and store credit, and exact output formatting.

    Coding & AlgorithmsTechnical Screen
  • StripeHardSoftware Engineer
    Subtract Blocked Periods from Allowed Deployment Windows

    Compute available deployment windows by merging allowed and blocked half-open intervals, subtracting overlaps, and returning maximal sorted nonempty ranges.

    Coding & AlgorithmsOnline Assessment
  • StripeHardSoftware Engineer
    Theme-Park Wristband Payments: Expiring Credits, Zone Fees, Refunds

    Process a chronological log of theme-park wristband events that spend expiring ride credits before a linked card, apply per-zone card surcharges, and split refunds between the card and new store credit.

    Coding & AlgorithmsTechnical Screensimulationevent-processinggreedy