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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 241–270 of 1080 results
- CoinbaseHardSoftware EngineerGenerate NFT metadata and ensure uniqueness
This question evaluates understanding of combinatorics, deterministic pseudo-random generation, and efficient enumeration for producing unique NFT metadata, measuring competency in algorithm design, state-space management, and handling large-scale outputs.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerGenerate Weighted Random NFTs with Updates
This question evaluates understanding of weighted random sampling, efficient data structures for maintaining and updating prefix sums, probabilistic reasoning about sampling distributions, and reproducible testing of randomized algorithms within the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerGenerate constrained NFT metadata
Generate constrained NFT metadata 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 & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerImplement Composable Range Iterators
This question evaluates understanding of iterator design, lazy evaluation, composable higher-order combinators (map, filter, zip, take, drop, chain), edge-case handling for forward/backward and negative-step ranges, overflow-safe termination, peekable semantics, iterator invalidation rules, and writing boundary-focused unit tests.
Coding & AlgorithmsOnsite - CoinbaseHardSoftware EngineerImplement Game Physics and Block Mining
This question evaluates implementation skills in deterministic game physics (discrete position and velocity updates with boundary and edge-case handling) alongside dependency-aware greedy selection for block construction, testing graph dependency resolution, greedy heuristics, and complexity analysis in the Coding & Algorithms domain, and is commonly asked to verify correctness under constraints, handling of boundary conditions, and trade-offs between optimality and performance. Level of abstraction spans both conceptual understanding (kinematic update rules, cycle detection, fee/size ratio reasoning) and practical application (implementing the tick update and returning a topologically ordered block while considering caching and scalability for large mempools).
Coding & AlgorithmsOnsite - CoinbaseMediumData ScientistImplement Plus One
This question evaluates array manipulation and numeric carry propagation skills, along with the ability to reason about time and space complexity when performing arithmetic on digit lists.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerImplement a Simple Banking Ledger
This question evaluates competence in designing an efficient, stateful ledger API and associated data structures, emphasizing correctness under invalid inputs, performance at scale, integer overflow handling, unit testing for edge cases, and transactional (atomic batch) behavior.
Coding & AlgorithmsOnsite - CoinbaseMediumBackend EngineerImplement a Stateful Trading Order Manager
This problem tests your ability to design a stateful system using hash-based sharding, efficient indexing, and robust state machine transitions for high-frequency financial orders.
Coding & AlgorithmsOnsiteHash TablesSystem DesignState Machines - CoinbaseMediumSoftware EngineerImplement custom iterator classes
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Implement custom iterator classes states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerImplement custom iterators and interfaces
Implement custom iterators and interfaces 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 & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerImplement iterators and write tests in Java
Implement iterators and write tests in Java 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 & AlgorithmsOnsite - CoinbaseMediumData ScientistIncrement Digit Array
This question tests the ability to handle array-based arithmetic and carry propagation logic, specifically addressing edge cases like array resizing.
Coding & AlgorithmsOnsiteArraysMathSimulation - CoinbaseMediumSoftware EngineerMaintain the Kth-Highest User Score with Updates and Removals
This problem tests your ability to maintain a dynamic set of scores and efficiently retrieve the k-th highest element using balanced data structures or ordered collections.
Coding & AlgorithmsOnsiteData StructuresBalanced BSTHash Map - CoinbaseHardSoftware EngineerMaximize block fee with transaction selection
This question evaluates algorithmic optimization and dependency-aware selection skills, focusing on resource-constrained selection (knapsack-like trade-offs) and graph-based dependency reasoning within the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerMaximize profit with transaction fee
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Maximize profit with transaction fee states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerMaximize profit with transaction fees
This question evaluates algorithm design skills, specifically understanding of dynamic programming and greedy strategies for optimizing profit under transaction fees, along with stateful decision-making and handling cost constraints.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerParse logs and generate NFT attributes
This problem tests your ability to parse structured log strings, group events by metadata, and perform weighted sampling across combinations of attributes.
Coding & AlgorithmsOnsiteParsingHashingProbability - CoinbaseMediumSoftware EngineerSchedule Fixed-Order Tasks with a Cooldown
Calculate the total days required to run a sequence of tasks in a strict, fixed order where identical tasks must be separated by a specified cooldown period.
Coding & AlgorithmsOnsiteArrayHash TableGreedy - CoinbaseMediumSoftware EngineerSelect transactions to maximize fees under size
This problem tests your ability to solve a variation of the 0/1 Knapsack problem where items have both a cost (size) and a value (fee).
Coding & AlgorithmsOnsiteDynamic ProgrammingOptimizationAlgorithms - CoinbaseMediumMachine Learning EngineerWrite SQL to rank top products per category
This question evaluates SQL proficiency in aggregation, time-based filtering, joining transactional and reference tables, and ranking/windowing techniques to compute and deterministically order product revenue with tie-breaking by product_id.
Coding & AlgorithmsOnsite - ConfluentMediumSoftware EngineerCheck Whether a Partially Filled 9x9 Sudoku Board Is Valid
A coding problem that asks whether a partially filled 9x9 Sudoku board is consistent, meaning no row, column or 3x3 box repeats a digit among its filled cells. It tests careful bookkeeping of row, column and box membership without attempting to solve the puzzle.
Coding & AlgorithmsOnsite - ConfluentMediumSoftware EngineerImplement File Tail and Sensor Health
This problem tests your ability to efficiently read the end of a growing file using file pointers and to implement a sliding time-window check for sensor heartbeat events.
Coding & AlgorithmsOnsiteI/OHash MapStreaming - ConfluentMediumSoftware EngineerImplement Tail and Find Monster Cost
This question evaluates competency in efficient file I/O and streaming techniques for implementing tail, and in graph search and shortest-path algorithms with path reconstruction for computing minimum monster cost in a grid.
Coding & AlgorithmsOnsite - ConfluentMediumSoftware EngineerMatch Argument Type Lists Against Function Signatures with Variadic Parameters
A coding problem about resolving function calls: given a library of function signatures, some variadic in their last parameter, return every function that accepts each queried list of argument types. It tests precise matching rules, indexing signatures for many queries and deterministic output ordering.
Coding & AlgorithmsOnsite - ConfluentMediumSoftware EngineerSolve Signature, File, and Queue Problems
This multi-part prompt evaluates skills in function signature and type matching, resource-constrained file I/O and streaming for large files, and data-structure design for randomized queues including multiset equality, synchronization, and compact run-length encodings.
Coding & AlgorithmsOnsite - ConfluentMediumSoftware EngineerValidate and Complete a Partially Filled 9x9 Sudoku Board
A coding problem that checks a partially filled 9x9 Sudoku board and completes it when possible. Solutions must detect givens that already break the row, column or box rules, recognize boards with no valid completion, and return a canonical completed grid, testing constraint checking and search.
Coding & AlgorithmsOnsite - CoreweaveMediumSoftware EngineerImplement web data fetch and storage tool
This question evaluates proficiency in HTTP client communication with token-based authentication, parsing structured responses into data models, relational database interaction including handling duplicate records, configuration management, and robust error handling and testing.
Coding & AlgorithmsOnsite - CoreweaveMediumSite Reliability EngineerQuery Machines and Mark Them Offline
This problem tests the ability to interact with external APIs, handle asynchronous operations with retries, and implement conditional filtering based on system metadata.
Coding & AlgorithmsOnsiteAPIAutomationError Handling - CoupangMediumSoftware EngineerFind shortest distance between two islands
This question evaluates understanding of grid-graph traversal and shortest-path concepts, including identification of connected components and reasoning about minimal bridging distance between regions.
Coding & AlgorithmsOnsite - CrowdstrikeMediumSoftware EngineerCount connected components in a binary grid
This problem tests your ability to model a 2D grid as a graph and use graph traversal algorithms like DFS or BFS to count distinct connected components.
Coding & AlgorithmsOnsiteGraphsDFSBFS
Coinbase
Confluent
Coreweave
Coupang
Crowdstrike