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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
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- 11
- Topics
- 8
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Showing 481–510 of 2336 results
- ByteDanceMediumSoftware EngineerDesign a Real-Time Auction Platform
This question evaluates a candidate's ability to design a real-time, high-throughput distributed system focusing on API design, concurrency control, ordering guarantees, idempotency, persistence of bid history and state transitions, and real-time push/update mechanisms.
System DesignOnsite - ByteDanceMediumSoftware EngineerDesign a Short-Video Recommendation System
This problem tests the ability to design a multi-stage recommendation pipeline that balances real-time personalization, system latency, and content diversity.
ML System DesignOnsiteSystem DesignRecommendation SystemsScalability - ByteDanceMediumSoftware EngineerDesign a payment system with real-time holds, batch settlement and safe retries
System design question: design a payment system that places real-time holds on funds and settles them in batches, then explain how retries avoid double charges. It probes idempotency at every hop, payment state machines, double-entry ledgers, consistency across an external processor, reconciliation, and recovery from specific failures.
System DesignOnsite - ByteDanceMediumSoftware EngineerDetect a Pythagorean Triple in an Integer Array
This problem tests the ability to optimize a brute-force approach into an efficient search using sorting and the two-pointer technique to satisfy a geometric condition.
Coding & AlgorithmsOnsiteArraysTwo PointersSorting - ByteDanceMediumSoftware EngineerExplain Why You Want to Change Roles
This question assesses the candidate's professional maturity, self-awareness, and ability to frame career transitions as proactive pursuits of growth rather than reactions to negative past experiences.
Behavioral & LeadershipOnsiteBehavioralCareer GrowthCommunication - ByteDanceMediumSoftware EngineerFind Maximum Candies With Two Types
This question evaluates algorithmic problem-solving with arrays, focusing on managing constraints on the number of distinct element types in a contiguous sequence and maintaining element frequency/state during a traversal.
Coding & AlgorithmsOnsite - ByteDanceMediumSoftware EngineerFind Words in a Character Grid
This question evaluates algorithm design for efficient multi-word search in a character grid, testing competencies in constrained graph traversal, managing large dictionaries, and selecting data structures for efficient lookup.
Coding & AlgorithmsOnsite - ByteDanceMediumSoftware EngineerFind the Minimum Window Containing a Multiset of Characters
This problem tests your ability to use the two-pointer sliding window technique combined with a frequency map to identify the smallest valid substring efficiently.
Coding & AlgorithmsOnsiteSliding WindowHash MapStrings - ByteDanceMediumSoftware EngineerFind the N-th Highest Bid in an Auction Log Without a Heap
Given an unordered list of auction bids, return the n-th highest one, treating two equal bid amounts as distinct entries, while a heap-based solution is off the table. Tests selection algorithms faster than full sorting, correct handling of duplicate values, and justifying the achieved time complexity.
Coding & AlgorithmsOnsitequickselectarraysselection - ByteDanceMediumSoftware EngineerHand-Write a Multi-Head Attention Layer: Projections, Head Splitting and Masking
Write a multi-head attention layer from scratch: project queries, keys and values, split them into heads, apply scaled dot-product attention with optional padding or causal masks, and merge the heads. It tests tensor shape discipline, numerical stability, and the cost of attention as sequence length grows.
Machine LearningOnsite - ByteDanceMediumSoftware EngineerImplement Sliding Windows and LRU Cache
This question evaluates algorithmic problem-solving and data-structure design, testing sliding-window and 2D submatrix reasoning for maximizing contiguous ones with bounded flips and the design of an LRU cache that enforces O(1) get/put semantics.
Coding & AlgorithmsOnsite - ByteDanceHardSoftware EngineerLeast Frequently Used (LFU) Cache
This problem tests the ability to design an O(1) time complexity cache that evicts the least frequently used items, using recency as a tie-breaker.
Coding & AlgorithmsOnsiteHash MapLinked ListData Structures - ByteDanceMediumSoftware EngineerMerge overlapping closed intervals into a sorted list of disjoint intervals
Coding problem: given closed integer intervals in any order, merge every group of overlapping or touching intervals and return the disjoint result sorted by start. It tests interval reasoning, correct handling of shared endpoints, duplicates and nested intervals, and a well-defined output order.
Coding & AlgorithmsOnsite - ByteDanceMediumSoftware EngineerModel Campaigns, Targeting, and Edit History for a Demand-Side Ad Platform
Model a demand-side ad platform with advertisers, campaigns, ad groups, ads, and creatives, including audience rules, edit history, and versioned publishing.
System DesignOnsite - ByteDanceMediumSoftware EngineerOrder Named Tasks by Dependencies, Choosing the Alphabetically Smallest Order
Given named tasks and before-and-after dependency pairs, return an order that satisfies every dependency, choosing the alphabetically smallest valid order, or an empty list when the dependencies contain a cycle. It tests topological sorting, cycle detection and deterministic tie-breaking.
Coding & AlgorithmsOnsite - ByteDanceEasySoftware EngineerPrepare for an SRE Systems Fundamentals Round
This question tests your understanding of Linux process management, memory utilization, and the practical troubleshooting steps required to handle a production service experiencing memory exhaustion.
Software Engineering FundamentalsOnsiteLinuxSREMemory Management - ByteDanceMediumSoftware EngineerReport the winner after each move on an n-by-n tic-tac-toe board
Coding problem: replay an n-by-n tic-tac-toe game from a list of moves and report after every move whether the player who just moved has filled a row, a column or either diagonal. It tests efficient win detection on large boards and careful handling of diagonal and anti-diagonal cells.
Coding & AlgorithmsOnsite - ByteDanceMediumSoftware EngineerResolve a Meaningful Disagreement
This question assesses the candidate's ability to navigate professional conflict through evidence-based reasoning, emotional intelligence, and a focus on collective project success.
Behavioral & LeadershipOnsiteConflict ResolutionCommunicationLeadership - ByteDanceMediumSoftware EngineerRunning Median After Each Number in a Data Stream
Numbers arrive one at a time from a stream; after each arrival, return the median of everything received so far, averaging the two middle values when the count is even. The problem tests keeping order statistics up to date efficiently as a data stream grows.
Coding & AlgorithmsOnsite - ByteDanceMediumSoftware EngineerSet Boundaries and Priorities in a High-Intensity Environment
This question assesses a candidate's ability to navigate high-pressure work environments by balancing personal sustainability with business objectives, focusing on prioritization strategies and escalation frameworks.
Behavioral & LeadershipOnsiteLeadershipPrioritizationCommunication - ByteDanceMediumSoftware EngineerSolve Search Speed and String Product
This pair of problems evaluates algorithm design and implementation skills, focusing on efficient search/optimization for constrained processing speed and manual arbitrary-precision string multiplication for very large integers.
Coding & AlgorithmsOnsite - C3 AIEasySoftware EngineerDesign a restaurant reservation system
This question evaluates skills in system architecture and engineering, including data modeling, API design, concurrency control to prevent double-booking, availability and scheduling logic, scalability under traffic spikes, and operational concerns like auditability and low-latency queries.
System DesignOnsite - Capital OneMediumSoftware EngineerAnalyze and Debug Virtual-Card Payment Rules
Implement and debug a rule-validation engine for virtual card authorization that accurately parses currency strings into integer cents and evaluates spending boundaries and merchant restrictions.
Software Engineering FundamentalsOnsitePythonData ParsingBoundary Conditions - Capital OneMediumSoftware EngineerBenefits of a Customer-Facing Chatbot for a Bank and Its Customers
A case-study opener asking what benefits a customer-facing chatbot would bring to a bank and to its customers. It tests whether you can tie each benefit to a concrete mechanism and metric, and weigh it against risks specific to banking such as wrong answers about money, authentication and privacy.
Product Design & StrategyOnsite - Capital OneMediumSoftware EngineerBuild a Banking System with Activity Rankings
This problem tests your ability to design a system that maintains account state and dynamically updates an ordered leaderboard of account activity using efficient data structures.
Coding & AlgorithmsOnsiteHash MapBalanced BSTDesign - Capital OneMediumSoftware EngineerBurner Card Numbers: Trade-offs, Hand Checks and a Buggy Validator
A three-part fintech case: weigh the trade-offs of disposable card numbers, check sample numbers by hand against format, Luhn and issuer-range rules, then find three bugs in a filter that rejects valid numbers and accepts invalid ones.
Software Engineering FundamentalsOnsitedebuggingluhnproduct-sense - Capital OneMediumSoftware EngineerDescribe leadership challenges and managing a difficult report
This question evaluates leadership, conflict-resolution, and team-management competencies in a software engineering context by probing examples of leading projects and managing a difficult or noncompliant direct report, and is categorized under Behavioral & Leadership.
Behavioral & LeadershipOnsite - Capital OneMediumSoftware EngineerDesign a Banking Component with Transfers and Activity Rankings
Design an in-memory banking service supporting account creation, deposits, atomic transfers, and activity rankings driven by a string-based command interface.
Software Engineering FundamentalsOnsiteDesignHash TableSorting - Capital OneMediumSoftware EngineerDesign a highly reliable account balance system
This question evaluates a candidate's ability to architect a highly reliable transactional account-balance service, testing competencies in data modeling and storage choice, API design for idempotency, concurrency and consistency mechanisms, replication/failover, partitioning for scale, and auditability.
System DesignOnsite - Capital OneHardSoftware EngineerDesign a scalable banking system
This question evaluates system design skills focused on distributed systems architecture, transactional integrity, strong consistency models, security and authentication, external payment and ATM integrations, data modeling, API design, concurrency control, and operational monitoring for financial platforms.
System DesignOnsite
C3 AI
Capital One