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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 931–960 of 1080 results

  • StripeMediumSoftware Engineer
    Assign Reviewers from Changed Files

    This question evaluates proficiency with version control diffs, repository library APIs, file I/O and CSV parsing, and data aggregation to map changed files to their owners.

    Coding & AlgorithmsOnsite
  • StripeMediumSoftware Engineer
    Build an Account Transfer Ledger

    Design and implement an in-memory account ledger that supports deposits, transfers, and platform-backed lending with automatic debt repayment.

    Coding & AlgorithmsOnsitedesignhash-tablestate-machine
  • StripeMediumSoftware Engineer
    Compute account balances with rejection and overdraft

    This question evaluates stateful transaction processing and aggregation skills, including per-(account,currency) balance maintenance, timestamp-based ordering, rejection rules, and overdraft coverage via a platform account.

    Coding & AlgorithmsOnsite
  • StripeMediumSoftware Engineer
    Compute balances with transaction fees and rejections

    This problem tests the ability to manage stateful financial records while enforcing conditional logic, fee structures, and balance validation.

    Coding & AlgorithmsOnsiteHash MapData ProcessingFinancial Logic
  • StripeMediumSoftware Engineer
    Compute currency conversions with graph algorithms

    Stripe software-engineer onsite coding question: design data structures and algorithms to compute currency conversions from pairwise exchange rates. It tests modeling currencies as a weighted directed graph, chaining rates with BFS/DFS to answer queries (or -1 when unknown), supporting online updates and many queries efficiently, detecting contradictions and arbitrage in cycles, and computing all rates against a base via topological sort on a DAG, with time and space complexity analysis.

    Coding & AlgorithmsOnsite
  • StripeMediumSoftware Engineer
    Convert bitmap into ASCII characters

    This question evaluates skills in binary-to-text data representation, bitmap rendering, and efficient string and array manipulation for output formatting.

    Coding & AlgorithmsOnsite
  • 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
    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
  • 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
    Weekly Maintenance Windows Across Time Zones: Find Usable Slots

    Combine recurring 'open' maintenance windows and 'blackout' periods, declared in different local time zones, into the next usable UTC slots after a notice period; tests interval merging, subtraction and week wrap-around.

    Coding & AlgorithmsOnsiteintervalssortingtime-zones
  • StubHubMediumSoftware Engineer
    Build Event Notification Engine

    This question evaluates a candidate's competency in modular software design and extensibility, algorithmic filtering and ranking, date arithmetic for birthday proximity, geospatial distance computation, and integration with notification services.

    Coding & AlgorithmsOnsite
  • StubHubMediumSoftware Engineer
    Design Composable Event Recommendations

    This problem tests your ability to design a flexible, object-oriented recommendation engine that allows for composable filtering and ranking logic using the strategy or decorator pattern.

    Coding & AlgorithmsOnsiteSystem DesignAlgorithmsOOP
  • StubHubMediumSoftware Engineer
    Implement a Composable Event Recommendation Engine

    This problem tests your ability to design a flexible, object-oriented recommendation pipeline using the Strategy and Composite patterns to handle multiple scoring rules and fallback logic.

    Coding & AlgorithmsOnsiteOOPStrategy PatternRecommendation Systems
  • SumologicMediumSoftware Engineer
    Solve substring and access-log problems

    This problem tests your ability to process log data and perform string manipulation by identifying users who visited a specific URL across multiple days and determining the longest common substring between two modified strings.

    Coding & AlgorithmsOnsiteStringsHashingDynamic Programming
  • TemuEasySoftware Engineer
    Find missing rank in a straight

    This question evaluates a candidate's ability to map and manipulate encoded card ranks, reason about consecutive sequences with Ace-as-low or Ace-as-high semantics, and identify a missing element within a constrained set.

    Coding & AlgorithmsOnsite
  • TemuEasySoftware Engineer
    Find next greater element for subset

    This question evaluates understanding of sequence analysis and array-processing competencies, including mapping elements between arrays, index lookup, and designing efficient order-dependent algorithms for the "next greater element" problem.

    Coding & AlgorithmsOnsite
  • TeslaMediumBackend Engineer
    Compute time to burn tree

    This question evaluates proficiency with tree algorithms, distance computation, and propagation modeling, testing the ability to reason about how a process spreads across parent-child relationships in a tree.

    Coding & AlgorithmsOnsite
  • TeslaEasySoftware Engineer
    Count the Ways to Decode a Numeric Cipher

    This problem tests your ability to solve a counting problem using dynamic programming by identifying overlapping subproblems in a sequence of numeric mappings.

    Coding & AlgorithmsOnsiteDynamic ProgrammingString ManipulationAlgorithms
  • TeslaHardSoftware Engineer
    Flatten a Linked List with Nested Side Branches into One Doubly Linked List

    A linked list whose nodes may each carry one side branch, with branches nested like a binary tree, must be flattened into a single doubly linked list with every branch spliced between its parent and the parent's original successor. It tests pointer rewiring, ordering rules for nested branches, and handling very deep nesting.

    Coding & AlgorithmsOnsite
  • TeslaEasySoftware Engineer
    Shortest Bridge to Connect Two Islands

    Tests matrix traversal techniques, specifically using DFS/BFS to identify connected components and multi-source BFS to find the shortest path between them.

    Coding & AlgorithmsOnsitegraphbfsdfs
  • The Trade DeskMediumSoftware Engineer
    Calculate Bowling Game Score

    This problem tests your ability to manage state and look-ahead logic when processing a sequence of events (bowling rolls) governed by specific conditional scoring rules.

    Coding & AlgorithmsOnsiteArraysLogicSimulation
  • ThumbtackMediumData Scientist
    Implement min, mean, median robustly

    This question evaluates implementation skills in basic descriptive statistics (min, mean, median), numerical stability in online aggregation methods, robust handling of edge cases like None/NaN and extreme numeric ranges, and algorithmic complexity reasoning in the Coding & Algorithms domain for a Data Scientist role.

    Coding & AlgorithmsOnsite
  • TikTokMediumData Scientist
    Compute Averages of Unique Numbers in Dictionary Lists

    This question evaluates data manipulation and aggregation skills, focusing on handling duplicate values within collections and computing numerical summaries of list data.

    Coding & AlgorithmsOnsite
  • TikTokMediumMachine Learning Engineer
    Determine frog reachability across stones

    This question evaluates dynamic programming, state-space reachability, and constrained transition reasoning, along with skills in hash-based memoization and time/space complexity analysis.

    Coding & AlgorithmsOnsite
  • TikTokMediumSoftware Engineer
    Find longest common subsequence length

    This question tests the ability to solve the Longest Common Subsequence (LCS) problem using dynamic programming, specifically focusing on building a 2D state table.

    Coding & AlgorithmsOnsiteDynamic ProgrammingStringsAlgorithms
  • TikTokMediumMachine Learning Engineer
    Find longest substring without repeating characters

    This question evaluates proficiency in string processing, duplicate-detection using appropriate data structures, and algorithmic complexity analysis within the Coding & Algorithms domain.

    Coding & AlgorithmsOnsite
  • TikTokMediumBackend Software Engineer
    Implement Hash Map Operations

    Build a hash map behind a deterministic operation stream with insertion, replacement, lookup, removal, and missing-key behavior. The specification avoids built-in map storage and fixes return ordering and value bounds for a future portable console implementation.

    Coding & AlgorithmsOnsite
  • TikTokMediumData Scientist
    Optimize Station Sequence for Maximum Car Output in Simulation

    This question evaluates a candidate's skills in scheduling and throughput optimization, including queue management and simulation-based performance analysis within constrained buffering and station sequencing.

    Coding & AlgorithmsOnsite
  • TikTokMediumBackend Software Engineer
    Process LRU Cache Operations

    Implement an LRU cache through a deterministic stream of put and get operations, including updates, misses, and eviction order. The prompt defines an exact portable function contract and examples suitable for a later four-language console handoff.

    Coding & AlgorithmsOnsite
  • TikTokHardSoftware Engineer
    Remove the Fewest Overlapping Intervals

    Tests greedy interval scheduling and sorting techniques to find the minimum number of intervals to remove so that no remaining intervals overlap.

    Coding & AlgorithmsOnsiteGreedySortingIntervals