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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 427 results

  • MicrosoftMediumSoftware Engineer
    Find the Best Connected Strength for Every Tree Node

    Compute the maximum weight connected subgraph containing each node in a tree with +1 and -1 neuron weights using rerooting dynamic programming.

    Coding & AlgorithmsOnline AssessmentTree DPRerooting DPGraphs
  • MicrosoftMediumSoftware Engineer
    Maximize Points by Deleting Values and Their Neighbors

    Tests dynamic programming and hash map aggregation to maximize points under adjacency constraints over a sparse range of values.

    Coding & AlgorithmsOnline Assessmentdynamic-programminghash-tablesorting
  • MicrosoftMediumSoftware Engineer
    Minimize the Largest Value When Picking at Least k Non-Adjacent Houses

    Pick at least k houses from a row without choosing two neighbors, so that the largest amount in any chosen house is as small as possible, and return that minimum. With up to 100,000 houses and values up to one billion, the task tests reasoning about a min-max objective under an adjacency constraint.

    Coding & AlgorithmsOnline Assessment
  • MicrosoftMediumSoftware Engineer
    Most Frequent Substring Under Distinct-Letter and Length Limits

    Find how often the most frequent eligible substring appears in a lowercase string, where an eligible substring has a length within a given range and no more than a set number of distinct letters. Overlapping occurrences count and inputs reach 100,000 characters, so the task tests efficient substring counting.

    Coding & AlgorithmsOnline Assessment
  • MicrosoftMediumSoftware Engineer
    Most Frequent Substring Within a Length Range and a Distinct-Letter Limit

    A string coding problem: among all substrings whose length falls in a given range and that use at most a given number of distinct letters, return how many times the most frequent one occurs. It tests handling overlapping occurrences and the distinct-letter limit, counting efficiently on strings of up to 100,000 characters, and returning zero when nothing qualifies.

    Coding & AlgorithmsOnline Assessment
  • MicrosoftMediumSoftware Engineer
    Solve binary-search knapsack & graph shortest path

    This question evaluates a candidate's ability to apply algorithmic optimization by using binary search instead of dynamic programming for a knapsack-style selection problem and to construct and compute shortest paths on a weighted graph from custom input.

    Coding & AlgorithmsOnline Assessment
  • MicrosoftMediumSoftware Engineer
    Solve budget queries and shortest path

    This question evaluates algorithmic design and data-structure selection for efficient preprocessing and query answering, along with shortest-path computation and graph representation choices, testing complexity analysis, large-input handling, path reconstruction, and edge-case reasoning in the Coding & Algorithms domain.

    Coding & AlgorithmsOnline Assessment
  • MicrosoftMediumSoftware Engineer
    Solve load balancing and perfect pairs

    This question evaluates algorithm design, correctness proof, and complexity analysis skills by combining a contiguous partitioning load‑balancing optimization with a combinatorial/number‑theoretic pair‑counting problem.

    Coding & AlgorithmsOnline Assessment
  • Morgan StanleyMediumSoftware Engineer
    Compute minimal cost to merge numbers

    Compute minimal cost to merge numbers 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 & AlgorithmsOnline Assessment
  • Morgan StanleyMediumSoftware Engineer
    Count decodings of a digit string

    Count decodings of a digit string 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 & AlgorithmsOnline Assessment
  • NVIDIAMediumSoftware Engineer
    Explain a shader compiler pipeline

    This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Explain a shader compiler pipeline states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Coding & AlgorithmsOnline Assessment
  • NVIDIAMediumSoftware Engineer
    Implement core graph algorithms for graphics

    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 core graph algorithms for graphics states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Coding & AlgorithmsOnline Assessment
  • NebiusMediumSoftware Engineer
    Solve four coding problems

    This set of problems evaluates algorithmic problem-solving skills focused on array and string manipulation, frequency and multiset reasoning, sliding-window and coverage concepts, and combinatorial counting for palindromability.

    Coding & AlgorithmsOnline Assessment
  • NetflixMediumSoftware Engineer
    Group users by same last K watched movies

    This question evaluates competency in set operations, grouping via maps/dictionaries, and algorithmic complexity analysis when comparing suffixes of ordered lists.

    Coding & AlgorithmsOnline Assessment
  • NetflixEasyMachine Learning Engineer
    Multiply Two Sparse Integer Matrices Given as Dense Grids

    Given two integer matrices stored as dense lists of rows in which most entries are zero, return their exact matrix product. It tests handling matrix dimensions correctly and exploiting sparsity to skip work on zero entries while still producing every entry of the result.

    Coding & AlgorithmsOnline Assessment
  • OpenAIHardSoftware Engineer
    Count Ordered Four-Shop Road Paths That Visit One Shop of Each Type

    Count the ordered routes through a town's road network that visit exactly one shop of each of four types, where consecutive shops must share a direct road and a route and its reverse count separately. Tests graph modeling, path enumeration under type constraints and careful counting on small graphs.

    Coding & AlgorithmsOnline Assessment
  • OpenAIMediumData Scientist
    Identify Bugs in Python Script for User Assignment

    This question evaluates a candidate's ability to detect bugs and data-quality risks in a Python script, testing competencies in code review, reproducible randomization, idempotency, logging, duplicate-exposure safeguards, and safe experiment-assignment logic.

    Coding & AlgorithmsOnline Assessment
  • OpenAIHardSoftware Engineer
    Microorganism Eating Simulation: Largest Survivor After Left-to-Right Rounds

    Simulate a row of microorganisms in which each one may eat a strictly smaller neighbor from a different family, with rounds resolved from left to right, and report the family and size of the largest survivor at equilibrium. It tests precise rule-following, list mutation during iteration, and careful per-round bookkeeping.

    Coding & AlgorithmsOnline Assessment
  • OptiverMediumSoftware Engineer
    Build and Validate a Binary Tree from Parent-Child Pairs

    This question evaluates understanding of tree and graph concepts, strict string parsing and validation, duplicate and cycle detection, and the construction of canonical S-expressions within the Coding & Algorithms category.

    Coding & AlgorithmsOnline Assessment
  • OptiverMediumSoftware Engineer
    Calculate Days Between Arbitrary Gregorian Dates

    This problem tests the ability to implement a calendar-based calculation algorithm, specifically handling leap year logic and modular arithmetic without iterating through every day.

    Coding & AlgorithmsOnline AssessmentAlgorithmsMathCalendar
  • OptiverMediumQuantitative Trader
    Compare two programs for equivalence

    This question evaluates program-equivalence reasoning skills, including understanding of language semantics (mutation, ordering stability, integer overflow/underflow, integer-division behavior), competency in comparing time and space complexity, and the ability to design property-based tests and edge cases.

    Coding & AlgorithmsOnline Assessment
  • OptiverMediumSoftware Engineer
    Count the Days Between Two Dates

    This question evaluates date arithmetic, calendar logic, string parsing, and correct leap-year handling as implementation competencies. It is commonly asked to assess algorithmic correctness and edge-case handling across month, year, and leap boundaries, falls under the Coding & Algorithms domain (date/calendar problems), and targets practical application rather than purely conceptual understanding.

    Coding & AlgorithmsOnline Assessment
  • OptiverMediumSoftware Engineer
    Courier Drone: Fastest Fixed-Distance Segment From Tick Logs

    From per-tick distance logs, find the highest average speed over any time span that covers exactly a target distance, where spans may start and end partway through a tick. Tests prefix sums, linear interpolation, and showing that an optimal span touches a tick boundary.

    Coding & AlgorithmsOnline Assessmentprefix-sumsbinary-searchsliding-window
  • OptiverMediumSoftware Engineer
    Days Between Two Calendar Dates

    This question evaluates proficiency in date and calendar arithmetic, specifically handling varying month lengths, leap year rules, and computing absolute differences between dates.

    Coding & AlgorithmsOnline Assessment
  • OptiverMediumSoftware Engineer
    Design a Balloon Festival Simulator

    This question evaluates proficiency in data structures, event-driven simulation, numerical aggregation of spatially varying fields, and time-based state tracking for mutable entities.

    Coding & AlgorithmsOnline Assessment
  • OptiverMediumSoftware Engineer
    Design a balloon stability tracker

    This question evaluates event-driven simulation, time-ordered state management, floating-point numerical evaluation of aggregate functions, and data-structure design for tracking dynamic object states and stability thresholds; it falls under the Coding & Algorithms domain, specifically simulation, event processing, and algorithmic data structures.

    Coding & AlgorithmsOnline Assessment
  • OptiverMediumSoftware Engineer
    Design a satellite propagation simulator

    Optiver software-engineer take-home: implement a SatelliteNetwork that simulates timed message propagation over an undirected graph and fires OnSatelliteReportedBack callbacks in deterministic order. It tests graph modeling, discrete-event simulation, priority-queue scheduling, and careful handling of 10s-per-hop forwarding and 30s report timing with tie-breaking by SatelliteId.

    Coding & AlgorithmsOnline Assessment
  • OptiverMediumQuantitative Trader
    Devise sequence-rule detection strategy

    This question evaluates pattern-recognition, algorithm design, statistical reasoning, and model-selection skills required for sequence inference and candidate-term prediction in the Coding & Algorithms / Data Science domain.

    Coding & AlgorithmsOnline Assessment
  • OptiverMediumSoftware Engineer
    Estimate expected comparisons in a BST

    Estimate expected comparisons in a BST 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 & AlgorithmsOnline Assessment
  • OptiverMediumSoftware Engineer
    Fastest 1000 Meters: Max Average Speed from 5-Second Distance Splits

    Given the meters a runner covers in each consecutive 5-second interval, find the highest average speed over any continuous stretch of exactly 1000 meters, where stretches may start or end mid-interval. Tests sliding-window reasoning, linear interpolation at boundaries and edge cases such as one interval exceeding 1000 meters.

    Coding & AlgorithmsOnline Assessment