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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 1951–1980 of 2810 results

  • OracleMediumSoftware Engineer
    Repeatedly Delete Runs of k Adjacent Equal Characters from a String

    Given a lowercase string and an integer k, repeatedly delete k adjacent equal characters, letting the remaining parts join and possibly form new runs, until no deletion is possible, then return what remains. It tests efficient simulation of cascading removals on strings of up to 100,000 characters.

    Coding & AlgorithmsTechnical Screen
  • OracleMediumSoftware Engineer
    Sum the Binary Numbers Spelled by Root-to-Leaf Paths in a 0/1 Tree

    Given a binary tree of 0 and 1 bits in level-order form, return the sum of the binary numbers spelled by every root-to-leaf path, reading the root as the most significant bit. The problem tests tree traversal, carrying an accumulated value down each path, and parsing a level-order serialization correctly.

    Coding & AlgorithmsTechnical Screen
  • OscarEasySoftware Engineer
    Design a Stateful Outreach Campaign Engine

    This problem tests the ability to design a resilient, stateful task scheduler capable of handling asynchronous external triggers (responses) and idempotent state transitions.

    System DesignTechnical ScreenDistributed SystemsState MachinesScheduling
  • OscarEasySoftware Engineer
    Find Clients Outside Provider Coverage

    This problem tests spatial data processing and efficient set operations to identify gaps in service coverage between clients and providers based on distance and specialty requirements.

    Coding & AlgorithmsTechnical ScreenAlgorithmsSpatialSet Operations
  • OtherHardSoftware Engineer
    Implement a multi-button click detector

    This question evaluates competency in real-time event stream processing, per-button state management, and timing-based classification of input events such as distinguishing single versus long presses.

    Coding & AlgorithmsTechnical Screen
  • Otter.AiMediumSoftware Engineer
    Evaluate Arithmetic Expressions

    This problem tests your ability to parse and evaluate a string representing a mathematical expression with basic operator precedence, typically requiring a stack-based approach or a recursive descent parser.

    Coding & AlgorithmsTechnical ScreenStackString ParsingMath
  • Otter.AiEasySoftware Engineer
    Extend a Key-Value Store with Commits and Explicit Rollover Semantics

    Design a versioned key-value store supporting staging, atomic commits, point-in-time snapshot reads, and automated rollover compaction.

    System DesignTechnical ScreenKey-Value StoreMVCCConcurrency
  • Otter.AiMediumSoftware Engineer
    Fixed-Width Text Display

    This question tests a candidate's ability to implement greedy line-packing and space-distribution algorithms, core string manipulation skills evaluated in software engineering interviews. It assesses practical application of text layout logic, including handling edge cases like single-word lines and justified formatting with uneven space distribution.

    Coding & AlgorithmsTechnical Screen
  • Otter.AiMediumSoftware Engineer
    Implement an Arithmetic Expression Evaluator

    This problem tests your ability to parse and evaluate mathematical expressions containing non-negative integers, addition, subtraction, multiplication, and nested parentheses using a stack-based approach or recursion.

    Coding & AlgorithmsTechnical ScreenStackParsingMath
  • Otter.AiMediumSoftware Engineer
    In-Memory Key-Value Store with Nested Transactions

    This problem tests the ability to implement a nested transactional key-value store using stack-based state management and scope shadowing.

    Coding & AlgorithmsTechnical ScreenHash MapStackTransactions
  • Otter.AiEasySoftware Engineer
    Validate Password Against Multiple Rules

    This problem tests your ability to efficiently iterate through a string while maintaining multiple state-based flags to satisfy diverse validation criteria.

    Coding & AlgorithmsTechnical ScreenStringsValidationAlgorithms
  • PalantirHardSoftware Engineer
    Design a scalable interview question bank

    Design a scalable interview question bank evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    System DesignTechnical Screen
  • PalantirMediumSoftware Engineer
    Discuss logistics and compensation

    Discuss logistics and compensation evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Behavioral & LeadershipTechnical Screen
  • PalantirMediumSoftware Engineer
    Group employees by shared interests

    This question evaluates a candidate's competency in organizing and querying collections, mapping relationships between entities, and reasoning about algorithmic time and space complexity within data structures and grouping operations.

    Coding & AlgorithmsTechnical Screen
  • PalantirEasySoftware Engineer
    Merge K Individually Sorted Integer Arrays Into One Sorted Array

    Merge k integer arrays, each sorted in non-decreasing order, into one sorted array that keeps every duplicate. The interviewer asked for the two-pointer method and divide and conquer, so the problem tests merging sorted sequences and how the cost grows with the number of arrays.

    Coding & AlgorithmsTechnical Screen
  • PalantirMediumSoftware Engineer
    Reflect on experiences and teamwork

    Reflect on experiences and teamwork evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Behavioral & LeadershipTechnical Screen
  • PalantirMediumSoftware Engineer
    Simulate a Growing Snake on a Grid and Report the Score After Every Move

    Simulate a snake moving on a rectangular grid, eating food that appears one piece at a time, and return the score after every move or -1 once the snake leaves the board or runs into itself. It tests precise state simulation, collision rules around the moving tail, and efficient tracking of the snake's body.

    Coding & AlgorithmsTechnical Screen
  • Palo Alto NetworksMediumSoftware Engineer
    Design a thread-safe high-QPS rate limiter

    A Palo Alto Networks system-design screen: design and implement a thread-safe, high-QPS rate limiter that enforces per-identity request quotas. The answer covers algorithm choice (token bucket vs. fixed/sliding window), atomic per-key state with locks or CAS, hot-path performance, bounded-memory eviction, distributed scaling (Redis+Lua, token leasing, consistent-hash partitioning), and rejection semantics.

    System DesignTechnical Screen
  • Palo Alto NetworksMediumSoftware Engineer
    Find minimum tanks to cover all houses

    This question evaluates a candidate's proficiency in algorithm design, specifically greedy strategies and string/array manipulation for coverage and optimization under local adjacency constraints.

    Coding & AlgorithmsTechnical Screen
  • ParadromicsMediumSoftware Engineer
    Compare RDBMS vs NoSQL and containers

    Evaluates mastery of data storage and scaling trade-offs (RDBMS vs NoSQL), virtualization and containerization concepts (VMs, Docker), orchestration features (Kubernetes), and language-level performance optimization (Python vs C++).

    Software Engineering FundamentalsTechnical Screen
  • ParadromicsMediumSoftware Engineer
    Compute ways to climb n steps

    This Coding & Algorithms question evaluates recursion and dynamic programming concepts by asking for the count of distinct ways to climb n steps, framed at an algorithmic/implementation level. It is commonly asked because it probes recognition of overlapping subproblems and the ability to optimize naive recursive approaches through subproblem reuse and improved time/space efficiency.

    Coding & AlgorithmsTechnical Screen
  • ParadromicsMediumSoftware Engineer
    Implement a hash table with put/get

    This question evaluates implementation and design skills for hash-based data structures, testing competency in data structures, hashing, collision handling, and achieving expected O(1) put/get performance in the Coding & Algorithms domain.

    Coding & AlgorithmsTechnical Screen
  • Paramount CommerceHardSoftware Engineer
    Design a Go music player with playlists

    This question evaluates object-oriented system design, API and data-structure modeling, state and concurrency management, persistence considerations, and algorithmic time/space complexity within a Go-based music player domain.

    System DesignTechnical Screen
  • Paramount CommerceMediumSoftware Engineer
    Explain motivations and company fit

    This question evaluates motivation, cultural and team fit, adaptability, and the ability to handle ambiguity while aligning technical work with business goals.

    Behavioral & LeadershipTechnical Screen
  • PatreonMediumSoftware Engineer
    Analyze Reports in a Nested Org Chart

    This problem tests your ability to model hierarchical tree structures and use post-order traversal to aggregate data across deep organizational levels efficiently.

    Coding & AlgorithmsTechnical ScreenTreesGraphsRecursion
  • PatreonEasySoftware Engineer
    Design org chart lookup with preprocessing

    This question evaluates skills in data structures and algorithms, specifically tree/forest representation, aggregation of subtree metrics, dynamic updates, and rigorous time and space complexity analysis.

    Coding & AlgorithmsTechnical Screen
  • PayPalMediumSoftware Engineer
    Assess HashMap vs ConcurrentHashMap

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

    Coding & AlgorithmsTechnical Screen
  • PayPalMediumSoftware Engineer
    Compare final, finally, finalize

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

    Coding & AlgorithmsTechnical Screen
  • PayPalMediumSoftware Engineer
    Compare write-back vs write-through caches

    This question evaluates understanding of caching policies and memory/storage hierarchy trade-offs, focusing on how write-back and write-through handle writes, coherence, durability, latency, bandwidth, dirty bits, write amplification, and power-loss risks.

    Coding & AlgorithmsTechnical Screen
  • PayPalMediumSoftware Engineer
    Contrast TCP vs UDP; detect loss

    This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Contrast TCP vs UDP; detect loss states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Coding & AlgorithmsTechnical Screen