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Software Engineer 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 2011–2040 of 2629 results
- RobinhoodMediumSoftware EngineerDesign a referral leaderboard with chain-based counts
This question evaluates a candidate's ability to model and compute transitive referral counts using graph-like structures and efficient data structures, testing skills in algorithm design, counting, and sorting within the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - RobinhoodEasySoftware EngineerDesign in-memory payment and friendship system
This question evaluates object-oriented design skills, stateful in-memory data structures, request processing, and correctness constraints such as friend relationships, unique request IDs, and atomic balance transfers.
Coding & AlgorithmsTechnical Screen - RobinhoodMediumSoftware EngineerFlatten Fractional-Share Inventory and Record Trade Logs
Process fractional-share buys and sells with exact hundredth units, whole-share market flattening, dollar-order conversion, and ordered inventory-perspective logs.
Coding & AlgorithmsTechnical Screen - RobinhoodMediumSoftware EngineerImplement string-based candlestick classifier
This question evaluates string parsing, streaming input processing, numeric validation, and attention to time/space complexity in the Coding & Algorithms category, focusing on efficient single-pass parsing and O(1) extra space constraints.
Coding & AlgorithmsTechnical Screen - RobinhoodMediumSoftware EngineerMaintain Fractional Stock Inventory Across Orders
Simulate sequential customer fractional buy and sell orders, using scaled integer arithmetic to maintain the firm's remaining inventory between 0 and 1 share while tracking whole-share market executions.
Coding & AlgorithmsOnsitesimulationmathhash-table - RobinhoodMediumSoftware EngineerParse Requests and Compute Balances
This problem tests your ability to parse structured text commands, manage relational state between users, and implement transactional logic with integrity constraints.
Coding & AlgorithmsOnsiteHash MapGraphParsing - RobinhoodMediumSoftware EngineerProduce a Deterministic Course Plan
Return the lexicographically smallest valid course order from prerequisite pairs, or report a cycle. Handle duplicate edges, malformed IDs, self-dependencies, empty course sets, and large graphs with deterministic topological sorting.
Coding & AlgorithmsOnsite - RobloxHardSoftware EngineerCount Distinct Hat Assignments and Maximize Hat Points
Count valid one-hat-per-person assignments and maximize assigned-hat points with exact counts, unique hat use, and bitmask or backtracking reasoning.
Coding & AlgorithmsOnsite - RobloxMediumSoftware EngineerData Center Rack Units: Can a Centered Equipment Bay Be Reserved?
Process an online stream of rack-unit reservations and span-availability checks over an infinite 1D coordinate line, answering each availability check with the data seen so far.
Coding & AlgorithmsOnline Assessmentbinary-searchonline-queriesarrays - RobloxMediumSoftware EngineerDesign 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 & AlgorithmsOnsite - RobloxMediumSoftware EngineerDetect robot state after movements
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Detect robot state after movements states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - RobloxMediumSoftware EngineerDetect runs and collapse a numeric grid
This question evaluates proficiency in 2D array manipulation, pattern detection for contiguous runs, and state simulation involving removal and gravity-like collapse of elements.
Coding & AlgorithmsOnsite - RobloxMediumSoftware EngineerFind largest digit-sum bucket size
This question evaluates a candidate's competency in combinatorial counting, digit-sum properties, and algorithmic optimization for range queries within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - RobloxMediumSoftware EngineerFind most frequent call path in logs
This problem tests your ability to parse structured log strings representing nested function calls into a hierarchical tree and identify the most frequently occurring execution path.
Coding & AlgorithmsTechnical ScreenStackHash MapString Manipulation - RobloxMediumSoftware EngineerFind the Longest Safe Straight-Line Movement on a Laser Grid
Find a robot's longest safe straight-line movement on a laser-covered grid, where only the initial cell is protected and laser rows and columns are blocked.
Coding & AlgorithmsOnline Assessment - RobloxMediumSoftware EngineerImplement Sliding-Window Rate Limiter
This problem tests your ability to implement a thread-safe rate limiter using a sliding window algorithm to ensure a user does not exceed a fixed number of requests within a rolling time frame.
Coding & AlgorithmsTechnical ScreenAlgorithmsData StructuresRate Limiting - RobloxMediumSoftware EngineerImplement a Log Rate Limiter
This problem tests your ability to design a thread-safe, time-windowed rate limiter using efficient data structures to track event timestamps.
Coding & AlgorithmsOnsiteHash TableDesignConcurrency - RobloxMediumSoftware EngineerImplement a sliding-window rate limiter
Evaluates the candidate's ability to design and implement an in-memory sliding-window rate limiter enforcing per-user and per-game constraints, focusing on correct request-acceptance semantics and efficient timestamp eviction; Category/domain: Coding & Algorithms; Level of abstraction: component-level algorithm and data-structure implementation.
Coding & AlgorithmsOnsite - RobloxMediumSoftware EngineerImplement queue-based rate limiter with multi-key limits
This question evaluates implementation and design skills around rate limiting, including rolling-window counters, multi-key constraints, and atomic updates, and falls under the Coding & Algorithms domain focused on practical application of algorithms and data structures.
Coding & AlgorithmsOnsite - RobloxMediumSoftware EngineerMatch-3 Grid: Find Horizontal and Vertical Runs, Then Clear and Drop Cells
A two-part grid problem modeled on a Match-3 game: report every horizontal and vertical run of three or more equal values in a fixed scan order, then clear the matched cells and let the remaining values in each column fall to the bottom. It tests precise run detection, ordering rules and grid simulation.
Coding & AlgorithmsTechnical Screen - RobloxMediumSoftware EngineerNumber Line Obstacles: Check Whether a Centered Block Can Be Built
Process operations on an infinite integer number line that either place an obstacle or ask whether a block centered at a point, reaching a given distance in each direction, is free of obstacles, and return the answers as a binary string. It tests efficient online range queries over large, sparse coordinates.
Coding & AlgorithmsOnline Assessment - RobloxMediumSoftware EngineerRandomly partition array into k segments
This question evaluates algorithm design, randomization techniques, and time/space complexity analysis within the Coding & Algorithms domain, focusing on partitioning an array into random non-empty segments.
Coding & AlgorithmsTechnical Screen - RobloxHardSoftware EngineerRank queries by prefix, frequency, and time
This question evaluates understanding of string processing, frequency aggregation, earliest-timestamp tracking, and efficient prefix-based retrieval for large datasets.
Coding & AlgorithmsTechnical Screen - RobloxMediumSoftware EngineerSimulate robot path and detect boundedness
This question evaluates the ability to simulate iterative movement and reason about repeated state transformations, testing competencies in algorithm design, cycle detection, and geometric reasoning; it falls under the Coding & Algorithms category.
Coding & AlgorithmsOnsite - RobloxMediumSoftware EngineerTrail Campsite Clearance: Online Pin and Range-Empty Queries
Process a stream of events that drop hazard pins at integer mile markers or ask whether a campsite centered at a marker with a given radius would be hazard-free, returning the answers as a string. Tests sparse-coordinate range counting with binary search and a Fenwick tree.
Coding & AlgorithmsOnline Assessmentfenwick-treecoordinate-compressionbinary-search - RoktEasySoftware EngineerImplement basic calculator with four operations
This question evaluates a candidate's ability to parse and evaluate arithmetic expressions, correctly apply operator precedence and left-to-right associativity, and handle integer arithmetic details such as truncating division, whitespace, and multi-digit numbers, and is commonly asked to assess implementation-level parsing and algorithmic reasoning. The category is Coding & Algorithms and the level of abstraction is practical application, focusing on coding an efficient evaluator that balances time and space constraints rather than purely conceptual theory.
Coding & AlgorithmsOnsite - RokuMediumSoftware EngineerCompute longest common subsequence length
This question tests the ability to solve the Longest Common Subsequence (LCS) problem using dynamic programming to optimize overlapping subproblems.
Coding & AlgorithmsOnsiteDynamic ProgrammingStringsAlgorithms - RubrikHardSoftware EngineerFind largest connected group of overlapping intervals
This question evaluates understanding of interval overlap modeling, graph connectivity, and algorithmic efficiency by requiring mapping time intervals to an undirected communication graph and identifying its largest connected component.
Coding & AlgorithmsOnline Assessment - RubrikHardSoftware EngineerValidate BFS order queries on a tree
This question evaluates understanding of BFS traversal, tree graph representation, and the ability to reason about allowable dequeue/enqueue orderings in a FIFO queue.
Coding & AlgorithmsOnline Assessment - RunloopMediumSoftware EngineerReturn a Topological Order or Detect a Cycle
This problem tests your ability to implement Kahn's algorithm for topological sorting while incorporating a priority-based tie-breaking mechanism to ensure deterministic output.
Coding & AlgorithmsTechnical ScreenGraphTopological SortHeap
Robinhood
Roblox
Rubrik