Coding & Algorithms interview questions

Showing 1321–1350 of 3276 results

• Implement a Spreadsheet With FormulasMedium

  This problem tests your ability to model cell dependencies using a directed graph, handle topological sorting for re-evaluation, and identify circular references.

  HarveyMachine Learning EngineerCoding & AlgorithmsTechnical Screen
• Implement an Integer Spreadsheet with FormulasMedium

  Design an in-memory integer spreadsheet supporting cell assignments, additive formulas with nested references, and dynamic recalculation of acyclic dependency chains.

  HarveySoftware EngineerCoding & AlgorithmsTechnical Screen
• Implement tag matcher and filesystemMedium

  This combined prompt evaluates string-processing and parsing skills for tag matching and design/implementation skills for an in-memory file system, measuring competencies in exact whole-word matching, case normalization, punctuation and duplicate handling, path parsing, hierarchical data structures, and file API behaviors.

  HarveyBackend EngineerCoding & AlgorithmsOnsite
• In-Memory File System: Create, Track Duplicates, and ListMedium

  Design an in-memory file system supporting directory creation, file creation with automated duplicate-name collision resolution, content retrieval, and directory listing.

  HarveySoftware EngineerCoding & AlgorithmsOnsite
• Spreadsheet Formula Engine with Cycle DetectionMedium

  Design an in-memory spreadsheet formula engine supporting cell assignments, formula evaluation with dependencies, and cycle detection. The question tests directed graph modeling, topological invalidation, and cycle detection algorithms.

  HarveySoftware EngineerCoding & AlgorithmsTechnical Screen
• Debug and extend obstacle-run statistics classesMedium

  This question evaluates object-oriented design, debugging, algorithmic reasoning, and probabilistic simulation competencies by requiring fixes to class behavior, implementation of aggregate statistics, and a Monte Carlo-based probability estimator.

  HeadwaySoftware EngineerCoding & AlgorithmsTechnical Screen
• Generate Every Letter String a Phone Keypad Digit Sequence Can SpellMedium

  Given a string of digits from 2 to 9, return every letter string those digits can spell on a standard phone keypad, in lexicographic order. It tests systematic enumeration of combinations, keys that carry four letters, and producing a deterministic output order.

  HeadwaySoftware EngineerCoding & AlgorithmsTechnical Screen
• Implement Journey Counter and Speeder DetectorHard

  This problem tests your ability to process time-series event data by grouping related actions, managing state across sequences, and performing geometric or threshold-based calculations.

  HeadwaySoftware EngineerCoding & AlgorithmsTechnical Screen
• Detect a Winner on a 3x3 Tic-Tac-Toe BoardHard

  This problem tests your ability to efficiently represent board states and implement win-condition logic for a grid-based game.

  HebbiaSoftware EngineerCoding & AlgorithmsOnsite
• Implement Ultimate Tic-Tac-ToeMedium

  This problem tests your ability to design a state-management system for a nested game board and implement recursive winner-detection logic.

  HebbiaSoftware EngineerCoding & AlgorithmsTechnical Screen
• Implement a Cache Snapshot PrinterMedium

  This question evaluates understanding of LRU cache semantics, data structures for maintaining recency and eviction, and techniques for serializing or compressing state by grouping identical values while preserving ordering.

  HebbiaSoftware EngineerCoding & AlgorithmsOnsite
• Detect a Reachable Negative CycleHard

  This problem tests the implementation of the Bellman-Ford algorithm to identify negative cycles reachable from a source vertex, specifically requiring careful handling of unreachable nodes to avoid incorrect cycle detection.

  Hive.AiSoftware EngineerCoding & AlgorithmsTechnical Screen
• Measure Water Trapped Between ElevationsHard

  This problem tests the ability to solve a classic dynamic programming/two-pointer challenge by calculating the volume of trapped water between bars of varying heights.

  Hive.AiSoftware EngineerCoding & AlgorithmsTechnical Screen
• Track the Median of a StreamHard

  This problem tests your ability to maintain sorted order in a streaming context using balanced data structures to achieve optimal time complexity for insertions and median retrieval.

  Hive.AiSoftware EngineerCoding & AlgorithmsTechnical Screen
• Validate Adding an Edge to a Directed Acyclic GraphHard

  This problem tests your ability to manipulate graph structures and implement reachability checks, specifically ensuring that adding an edge to a Directed Acyclic Graph (DAG) maintains its acyclic property.

  Hive.AiSoftware EngineerCoding & AlgorithmsTechnical Screen
• Convert a Column Number to an Excel-Style LabelMedium

  Convert one-based spreadsheet columns into A-through-Z and AA-through-ZZ labels, with correct handling of multiples of 26.

  HouzzSoftware EngineerCoding & AlgorithmsOnline Assessment
• Design a bank with scheduled payments and mergesMedium

  This question evaluates data-structure and algorithm design competencies with emphasis on concurrency, time-based scheduling, aggregation (TopK), transactional consistency, idempotency, and merge semantics for an in-memory banking service, falling under the Coding & Algorithms and system-design domain.

  HubSpotSoftware EngineerCoding & AlgorithmsOnline Assessment
• Design and implement a bank account systemMedium

  This question evaluates a candidate's skills in system design, data modeling, transactional integrity, concurrency control, idempotency, API design, and algorithmic complexity for implementing a minimal banking service.

  HubSpotSoftware EngineerCoding & AlgorithmsOnline Assessment
• Find a special person using knows(a,b)Easy

  This question evaluates algorithmic reasoning about pairwise relation inference using an oracle-style knows(a, b) API and the ability to minimize API calls, testing skills in graph modeling and asymptotic analysis.

  HubSpotSoftware EngineerCoding & AlgorithmsOnsite
• Find spammer with minimal hasMessaged callsMedium

  Find the "spammer" account that messaged every other account but received from none, using only a hasMessaged(a, b) oracle. This is the classic find-the-celebrity problem inverted, solved with a two-phase elimination-then-verify algorithm in O(n) oracle calls and O(1) extra space, with full correctness proof and edge-case handling.

  HubSpotSoftware EngineerCoding & AlgorithmsOnsite
• Implement account CRUD and transferMedium

  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 Implement account CRUD and transfer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

  HubSpotSoftware EngineerCoding & AlgorithmsOnline Assessment
• Validate hiring request under role constraintsMedium

  This problem tests your ability to manage state mapping and validate cardinality constraints using hash maps, requiring efficient lookups to ensure hiring requests remain within predefined role limits.

  HubSpotSoftware EngineerCoding & AlgorithmsTechnical Screen
• Approach verbose data-structure designMedium

  This question evaluates a candidate's ability to design and implement complex data structures, testing algorithmic reasoning, time/space complexity analysis, state modeling, and organization of code and tests.

  Hudson River TradingSoftware EngineerCoding & AlgorithmsTechnical Screen
• Ball Position in a Tilting Maze After Timed Tilt EventsEasy

  Live coding simulation problem: a ball sits in a grid maze on a board that can tilt up, down, left or right or lie flat, and timed events change the tilt. Return the ball's cell at an end time that can be very large. It tests precise timing rules, wall handling and movement code that scales to long time spans.

  Hudson River TradingSoftware EngineerCoding & AlgorithmsTechnical Screen
• Calculate Completion Time for a Single-Server Reactor QueueMedium

  Simulate a single-threaded reactor queue with a bounded buffer to compute the completion timestamp or drop status for each incoming task.

  Hudson River TradingSoftware EngineerCoding & AlgorithmsTechnical Screen
• Check Root-To-Leaf Target Sums In A Binary TreeEasy

  This question tests your ability to traverse a binary tree using depth-first search (DFS) or breadth-first search (BFS) while tracking path accumulators and accurately identifying valid leaf nodes.

  Hudson River TradingSoftware EngineerCoding & AlgorithmsTechnical Screen
• Count Digit-Reversal Equivalent PairsMedium

  Count pairs of indices in an integer array whose values share the same canonical digit-reversal form.

  Hudson River TradingSoftware EngineerCoding & AlgorithmsTechnical Screen
• Count Length-3 Chat Substrings with a VowelMedium

  Count the number of distinct length-3 alphabetical substrings in a chat message that contain at least one vowel.

  Hudson River TradingSoftware EngineerCoding & AlgorithmsTechnical Screen
• Count People Reaching the BoundaryEasy

  This question evaluates algorithmic simulation and event-driven modeling skills, specifically handling discrete versus continuous time, visibility constraints relative to a stationary watcher that changes facing direction, and boundary conditions for state transitions.

  Hudson River TradingMachine Learning EngineerCoding & AlgorithmsOnsite
• Count Smaller Numbers with Only Zero and One in Base FourMedium

  Count the number of positive integers strictly less than n whose base-4 representation consists only of the digits 0 and 1.

  Hudson River TradingData ScientistCoding & AlgorithmsOnline Assessment