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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 3061–3090 of 3276 results

  • UpstartMediumData Scientist
    Design Algorithm for Longest Substring with K Distinct Characters

    This question evaluates proficiency in string-processing and sliding-window algorithm patterns, assessing competency in designing efficient solutions and managing data structures to track distinct elements and reason about time and space complexity.

    Coding & AlgorithmsOnsite
  • UpstartMediumSoftware Engineer
    Find Maximum Eastbound City Visits and Parse CSV

    Tests string parsing for CSV records with quoted fields and escaped delimiters, followed by finding the longest valid subsequence of eastbound city visits with lexicographical tie-breaking.

    Coding & AlgorithmsOnline AssessmentDynamic ProgrammingString ParsingAlgorithms
  • UpstartMediumSoftware Engineer
    Find max word letter span

    This question evaluates proficiency in string processing, character mapping, and algorithmic analysis by requiring computation of per-word letter spans while accounting for case normalization, punctuation handling, ties, duplicates, and edge-case word forms.

    Coding & AlgorithmsTechnical Screen
  • UpstartMediumSoftware Engineer
    Find the Minimum Absolute Difference

    This problem tests your ability to efficiently find the minimum absolute difference between any two elements in an array, requiring an understanding of sorting and linear scans.

    Coding & AlgorithmsOnline AssessmentSortingArraysAlgorithms
  • UpstartMediumSoftware Engineer
    Implement Byte Formatting and Cafeteria Billing

    This problem tests your ability to implement custom string formatting logic for file sizes and a stateful simulation of a billing system with capacity limits.

    Coding & AlgorithmsOnline AssessmentStringsSimulationHashing
  • UpstartEasyData Scientist
    Implement factorial and count trailing zeros

    This question evaluates understanding of factorial computation and algorithmic techniques, including iterative versus recursive approaches, handling large integers and recursion constraints, and efficient counting of trailing zeros via number-theoretic reasoning.

    Coding & AlgorithmsOnsite
  • UpstartEasySoftware Engineer
    Remove Duplicate Integers While Preserving Order

    This problem tests your ability to filter elements from an array while maintaining the original sequence and ensuring optimal time complexity using auxiliary data structures.

    Coding & AlgorithmsOnline AssessmentArraysHash TableData Structures
  • UpstartMediumSoftware Engineer
    Remove Duplicates While Preserving First-Appearance Order

    Return each array value once in its original first-appearance order, using membership tracking without sorting the result.

    Coding & AlgorithmsOnline Assessment
  • UpstartEasySoftware Engineer
    Report Where a Value Appears

    Check whether a target value appears at an even index, an odd index, the first half, and the second half of an even-length list in a single scan.

    Coding & AlgorithmsOnline AssessmentArrayFundamentalsEarly Termination
  • UpstartEasySoftware Engineer
    Scale Ingredient Quantities

    This problem tests string parsing and manipulation, specifically isolating numeric prefixes from measurement units and descriptive text while maintaining the relative structure of ingredient lists.

    Coding & AlgorithmsOnline AssessmentStringsParsingData Manipulation
  • UpstartMediumSoftware Engineer
    Scale Recipe Quantities Without Changing Product Descriptions

    Multiply only the leading quantity in each ingredient line, preserving recipe order, product wording, and numbers inside descriptions.

    Coding & AlgorithmsOnline Assessment
  • UpstartMediumSoftware Engineer
    Solve Reported OA Coding Problems

    This prompt evaluates algorithmic problem-solving skills across grid-based ordering constraints, array pair-sum identification, and minimum-difference computation, testing knowledge of data structures, time/space complexity, and correctness conditions.

    Coding & AlgorithmsOnline Assessment
  • UpstartMediumSoftware Engineer
    Solve remembered OA coding tasks

    This set of problems evaluates skills in data aggregation and ordering (identifying top averages), computational geometry and extrema calculation (axis-aligned bounding rectangle), and grid constraint validation and consistency checking (partially filled 9x9 number board).

    Coding & AlgorithmsOnline Assessment
  • UpstartMediumSoftware Engineer
    Sum Multiples of Three, Five, or Seven

    Calculate the sum of all unique positive integers strictly less than a given limit that are divisible by 3, 5, or 7. The problem requires using the Principle of Inclusion-Exclusion to achieve an O(1) time complexity capable of handling inputs up to 10^18.

    Coding & AlgorithmsOnline Assessmentmathinclusion-exclusionarithmetic-series
  • ValonMediumSoftware Engineer
    Design an In-Memory Database

    This question evaluates a candidate's skills in data modeling, in-memory data structures, index design, and query/filter semantics for a flexible schema-less record store.

    Coding & AlgorithmsTechnical Screen
  • ValonHardSoftware Engineer
    Implement an In-Memory Query Engine

    Design and implement an in-memory query engine capable of ingesting records and executing structured queries with comparison, membership, and logical operators.

    Coding & AlgorithmsTechnical ScreenData StructuresDesignRecursion
  • ValonHardSoftware Engineer
    Implement an in-memory SQL-like table

    This problem tests your ability to design a flexible, in-memory table structure that supports dynamic schema definition, data storage, and basic relational query operations.

    Coding & AlgorithmsTechnical ScreenData StructuresAPI DesignAlgorithms
  • VantaMediumSoftware Engineer
    Design streaming test logger and queries

    This question evaluates a candidate's ability to design streaming data structures and time-series algorithms to track state transitions and compute interval queries, covering competencies in online/event-processing algorithms, interval overlap aggregation, and algorithmic complexity analysis within the Coding & Algorithms domain.

    Coding & AlgorithmsTechnical Screen
  • VantaMediumSoftware Engineer
    Design test-run logging and query functions

    This question evaluates proficiency in time-series logging, event-driven state transitions, interval and sliding-window algorithms, and efficient data-structure design for streaming updates.

    Coding & AlgorithmsTechnical Screen
  • VantaMediumSoftware Engineer
    Implement Adjacent-Line Uniq

    Implement a Unix-style adjacent-line deduplication function that groups consecutive identical lines, supports case-insensitive matching, and filters output based on run counts in linear time.

    Coding & AlgorithmsOnsitetwo-pointersstringsimulation
  • VantaEasySoftware Engineer
    Implement a Unique Lines Command

    Implement a streaming generator that mimics the Unix `uniq` command by collapsing consecutive duplicate lines with options for counting and case-insensitivity.

    Coding & AlgorithmsOnsiteStreamingString ProcessingFile I/O
  • VantaMediumSoftware Engineer
    Order Classes by Prerequisites with Recursive DFS

    Build a deterministic prerequisite ordering with recursive depth-first search. Handle disconnected classes and detect dependency cycles by tracking both active and completed nodes.

    Coding & AlgorithmsOnsite
  • Veeva SystemsMediumSoftware Engineer
    Compute build order from dependencies

    Compute build order from dependencies 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
  • VercelMediumSoftware Engineer
    Count Hits in the Past Five Minutes

    Implement a five-minute hit counter with ordered timestamped operations, repeated hits, and an explicit 300-second expiration boundary.

    Coding & AlgorithmsTechnical Screen
  • VercelEasySoftware Engineer
    Group Tree Nodes into Layers from the Leaves Up to the Root

    Given a rooted tree described as an undirected edge list, return its nodes in layers from the leaves up to the root, where each node sits one layer above its highest child and each layer is sorted. It tests rooting a tree from a graph, bottom-up ordering, and handling very deep, path-shaped trees.

    Coding & AlgorithmsOnsite
  • VercelMediumSoftware Engineer
    Search Recorded Metrics by Name, Tags, and Recency

    Design an in-memory metric storage and querying system that allows recording time-series metrics with key-value tags and retrieving the most recent matches filtered by name and tags.

    Coding & AlgorithmsOnsitedata-structureshash-tablesorting
  • VerkadaHardSoftware Engineer
    Find and Merge Camera Alert Intervals

    This question evaluates understanding of time-series processing, interval detection, and interval-merging algorithms, including handling thresholds, touching intervals, and open-ended alerts.

    Coding & AlgorithmsTechnical Screen
  • VerkadaMediumSoftware Engineer
    Find motion intervals above threshold

    This question evaluates understanding of time-series data processing and interval detection, focusing on grouping timestamped motion readings that exceed a numeric threshold and managing contiguous active segments.

    Coding & AlgorithmsTechnical Screen
  • VerkadaMediumSoftware Engineer
    Find the Super Admin User Who Can Access Every Camera Through Nested Groups

    Given permission triples linking users, groups and cameras, find the user who can access every camera through direct ownership or through nested, possibly cyclic group memberships. It tests modeling permissions as a directed graph, reachability that tolerates membership cycles, and edge cases such as an input with no cameras or a group that covers everything.

    Coding & AlgorithmsTechnical Screen
  • VerkadaMediumSoftware Engineer
    Find user who can access every camera

    This problem tests your ability to model hierarchical access control systems as a directed graph and determine reachability using graph traversal techniques like BFS or DFS.

    Coding & AlgorithmsOnsiteGraphsBFS/DFSReachability