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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 661–690 of 2810 results

  • Capital OneMediumSoftware Engineer
    Design a Credit Card System: Authorization, Fraud, Bureau Reports, Limit Increases

    A system design question for a credit card platform covering customer login, real-time payment authorization with fraud checks, monthly credit bureau reporting, a spending overview, and instant credit limit increase decisions. It tests laying out entities, services and read and write paths before choosing deep dives.

    System DesignTechnical Screen
  • Capital OneMediumSoftware Engineer
    Design a transaction class for deposits/withdrawals

    This problem tests your ability to design a robust, thread-safe class for managing bank account transactions, focusing on atomicity and data consistency.

    Software Engineering FundamentalsTechnical ScreenConcurrencyObject-Oriented DesignThread-Safety
  • Capital OneMediumSoftware Engineer
    In-Memory Banking System: Deposits, Transfers, Top-N Activity, Test Harness

    An object-oriented coding exercise that builds an in-memory banking system in stages: creating accounts and deposits, transfers between accounts, and ranking the top N accounts by activity. It also tests writing a harness that runs string-array test commands, and confirming whether activity means operation count or amount moved.

    Software Engineering FundamentalsTechnical Screen
  • Capital OneMediumSoftware Engineer
    Merchant-Locked Payment Codes: Trade-offs and a Buggy Checker

    A three-part fintech case on merchant-locked, single-merchant payment codes: discuss their trade-offs for cardholder and issuer, hand-validate sample codes against a digit-position rule table, then find and fix three planted bugs in a flawed validator.

    Software Engineering FundamentalsTechnical Screencase-interviewdebuggingvalidation-logic
  • Capital OneMediumSoftware Engineer
    Remove nodes with a given value

    This problem tests your ability to manipulate singly linked lists, specifically handling edge cases like removing head nodes and reassigning pointers in a single pass.

    Coding & AlgorithmsTechnical ScreenLinked ListPointersRecursion
  • Capital OneMediumSoftware Engineer
    Sort Matrix Diagonals By Their Values

    Tests matrix traversal along anti-diagonals, string formation, and custom multi-key sorting with deterministic tie-breaking.

    Coding & AlgorithmsTechnical Screenmatrixsortingstrings
  • Capital OneMediumSoftware Engineer
    Virtual Card Numbers Case: Trade-offs, Payment Validation Rules, Debugging

    A three-stage case interview on virtual credit card numbers. It covers the benefits and problems of virtual cards for cardholders and the issuer, a hand walkthrough that validates payments against digit-by-digit card number rules, and debugging messy validator code for inverted boolean operators and boundary errors.

    Software Engineering FundamentalsTechnical Screen
  • CerebrasHardSoftware Engineer
    Design a Multi-Channel Message Queue

    This question evaluates understanding of data modeling for multi-tag messages, set-based subscription semantics, scalable system design, and algorithmic complexity for operations such as enqueue, dequeue, subscribe/unsubscribe, and intersection queries.

    System DesignTechnical Screen
  • CerebrasMediumSoftware Engineer
    Explain Learning and Conflict Approaches

    This question evaluates a candidate's ability to learn in ambiguous technical domains, manage disagreements with senior colleagues, and adopt efficient learning approaches—assessing adaptability, communication, prioritization, and leadership competencies.

    Behavioral & LeadershipTechnical Screen
  • CerebrasMediumSoftware Engineer
    Implement Binary Search in C++

    This question evaluates proficiency in implementing binary search in C++, focusing on iterative control flow, correct handling of not-found cases, boundary conditions, and understanding of algorithmic correctness.

    Coding & AlgorithmsTechnical Screen
  • CerebrasMediumSoftware Engineer
    Implement and Optimize Vector Multiplication

    This question evaluates a candidate's ability to implement vector–vector multiplication and to reason about performance optimizations and sparse data structures, assessing competencies in algorithm design, parallel computing, memory hierarchy, and numerical operations.

    Coding & AlgorithmsTechnical Screen
  • ChalkMediumSoftware Engineer
    Compute rainwater accumulation on a height grid

    Tests the ability to simulate 2D fluid accumulation using priority-queue-based graph traversal (similar to Dijkstra's algorithm) to track spilling boundaries.

    Coding & AlgorithmsTechnical Screenheapbfsgraph
  • Character.AIMediumSoftware Engineer
    Find Shortest Covering Substring

    This problem tests your ability to use the sliding window technique and hash maps to find the smallest window in a string that contains all characters of a target pattern.

    Coding & AlgorithmsTechnical ScreenSliding WindowHash MapTwo Pointers
  • ChariotMediumSoftware Engineer
    Explore an HTTP Maze

    This question evaluates the ability to integrate HTTP-based APIs with graph traversal and state management, covering concepts such as breadth-first exploration for shallow-first search, cycle avoidance, transient error handling, and key-lock resource constraints.

    Coding & AlgorithmsTechnical Screen
  • Charta HealthMediumSoftware Engineer
    Make Token-Bucket Admission Safe Across Threads

    Tests your ability to implement a thread-safe token bucket rate limiter with lazy refill, monotonic time tracking, and blocking admission control.

    Software Engineering FundamentalsTechnical Screenconcurrencymultithreadingrate-limiting
  • Chicago Trading CompanyMediumSoftware Engineer
    Build an Ordered Latest-Quote Container

    Build an insertion-ordered container that stores only the latest quote for each stock symbol. Support expected O(1) push, pop, and size operations while updating bid and ask values without changing a symbol's original position and safely rejecting malformed commands.

    Coding & AlgorithmsTechnical Screen
  • Chicago Trading CompanyMediumSoftware Engineer
    Describe Growth, Mistakes, and Obstacles

    This question assesses the candidate's ability to reflect on professional setbacks, demonstrate accountability, and translate constructive criticism into measurable skill growth.

    Behavioral & LeadershipTechnical ScreenBehavioralAccountabilityMentorship
  • Chicago Trading CompanyMediumSoftware Engineer
    Implement a Constant-Time Simple Moving Average

    Implement a fixed-window simple moving average with O(1) processing for every valid add and query. Maintain a rolling sum and bounded queue, average the samples available before the window fills, and return deterministic results for empty, malformed, or unknown operations.

    Coding & AlgorithmsTechnical Screen
  • Chicago Trading CompanyMediumSoftware Engineer
    Implement a Unique Pointer and Vector

    This problem tests your understanding of C++ RAII, move semantics, template metaprogramming, and manual memory management by requiring the implementation of a scoped unique-ownership pointer and a custom dynamic array container.

    Software Engineering FundamentalsTechnical ScreenC++RAIIMemory Management
  • ChimeEasySoftware Engineer
    Design load balancing, caching, and idempotent APIs

    This question evaluates a candidate's competency in designing scalable, reliable backend architectures, specifically focusing on load balancing strategies, multi-layer caching, and idempotent API design.

    System DesignTechnical Screen
  • ChimeEasySoftware Engineer
    Explain sync/async, Go concurrency, SQL vs NoSQL

    This question evaluates understanding of execution models (synchronous vs asynchronous and blocking vs non-blocking), Go concurrency patterns (goroutines, channels versus shared-memory with locks), and database paradigms (SQL vs NoSQL) relevant to backend engineering.

    Software Engineering FundamentalsTechnical Screen
  • ChimeMediumSoftware Engineer
    Implement single-tab browser history navigation

    This question evaluates understanding of data structures, stateful API behavior, amortized time complexity, set membership tracking, and edge-case handling for implementing browser-like history navigation in the coding & algorithms domain.

    Coding & AlgorithmsTechnical Screen
  • CircleHardSoftware Engineer
    Implement Recipe Storage CRUD

    This question evaluates the ability to design and implement in-memory data structures and APIs for CRUD operations, covering skills such as ID generation and parsing, string handling for case-insensitive uniqueness constraints, data modeling, and preserving original value casing.

    Coding & AlgorithmsTechnical Screen
  • CircleMediumSoftware Engineer
    In-Memory Bank System With Top-N Activity Ranking and Expiring Pending Transfers

    Implement an in-memory banking class in stages: create accounts, deposit and pay, rank the top n accounts by transaction activity, and support transfers that hold funds until the recipient accepts within a time window or they are refunded. Tests state modeling, validation, and timestamp-driven expiry.

    Software Engineering FundamentalsTechnical Screen
  • CiscoHardSoftware Engineer
    Formalize a Minimum-Trip Transport Puzzle with Horses and Ladders

    Model a horses-and-ladders transport puzzle by clarifying legal moves, tracking resource state, and proving a minimum-trip plan is optimal.

    Statistics & MathTechnical Screen
  • CiscoHardSoftware Engineer
    Implement an LFU Cache

    This problem tests your ability to design a data structure that supports O(1) insertions and lookups while managing cache eviction based on access frequency and recency.

    Coding & AlgorithmsTechnical ScreenHash TableLinked ListDesign
  • CiscoEasySoftware Engineer
    Longest Substring Without Repeated Characters

    This problem tests string manipulation, hash map usage, and the sliding window technique to find a specific substring based on unique character constraints.

    Coding & AlgorithmsTechnical ScreenSliding WindowStringsHash Map
  • CiscoEasySoftware Engineer
    Reason About C Pointer and Array Declarations

    This question tests the ability to parse complex C declarations and understand memory layout, pointer arithmetic, and the differences between pointers and arrays.

    Software Engineering FundamentalsTechnical ScreenCPointersMemory
  • CitadelMediumSoftware Engineer
    Choose 200 of a Million Records to Label, Improving on Uniform Random Sampling

    Tests the ability to define data informativeness under extreme budget constraints (selecting 200 out of 1,000,000 records) and design a scalable, one-shot sampling strategy that outperforms uniform random sampling in coverage and diversity.

    Statistics & MathTechnical ScreenActive LearningSamplingClustering
  • CitadelMediumSoftware Engineer
    Compute BBO and NBBO from order data

    This question evaluates a candidate's skill in designing efficient data structures and algorithms for aggregating and querying order-book data, including computing best bid/ask prices and summing quantities at those prices.

    Coding & AlgorithmsTechnical Screen