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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
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- 546
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- 11
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- 8
- Languages
Showing 2761–2790 of 5874 results
- InstacartMediumSoftware EngineerMake a Variable Resolver Safe for Production Use
Analyze variable-resolution complexity and improve stack safety, validation, cycle detection, error reporting, caching, and update consistency.
Software Engineering FundamentalsOnsite - InstacartMediumSoftware EngineerOptimize file reading and expression DFS
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Optimize file reading and expression DFS states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsHR Screen - InstacartMediumSoftware EngineerOptimize file reads for password validation
This question evaluates proficiency in on-disk file I/O, streaming algorithms, offline indexing for sublinear lookups, and system-level performance considerations for validating credentials in large files.
Coding & AlgorithmsHR Screen - InstacartMediumSoftware EngineerParse Pipe-Delimited Order Lines: Totals, Cheapest Promotion per SKU, Aisle Ordering
A three-part coding exercise that parses pipe-delimited order lines with prices in cents, applies the cheapest of several percentage and buy-X-get-Y promotions per SKU, and orders products by aisle with frozen items last. It tests input validation, exact money arithmetic, extensible pricing rules and composite sorting.
Software Engineering FundamentalsOnsite - InstacartMediumSoftware EngineerParse a password from a matrix
This question evaluates proficiency in grid traversal, sequence-driven state tracking, string manipulation, and boundary/obstacle validation while requiring time and space complexity reasoning.
Coding & AlgorithmsOnsite - InstacartMediumSoftware EngineerParse password from indexed matrix file
This question evaluates file parsing, matrix indexing with a specified coordinate origin, handling multiple indexed blocks, and string assembly into an ordered password, testing competencies in file I/O, coordinate transformations, and robust input handling.
Coding & AlgorithmsOnsite - InstacartMediumSoftware EngineerPast Project Deep Dive: Technical Trade-offs and Handling a Technical Disagreement
A behavioral round built around a past project: walk through it, explain a significant technical trade-off and why you chose it, and describe how you handled a disagreement over a technical decision. It tests ownership, decision-making with evidence and collaboration, rewarding specific detail over general statements.
Behavioral & LeadershipTechnical Screen - InstacartMediumSoftware EngineerPivot data without date libraries
This question evaluates a candidate's competency in data manipulation and transformation, specifically pivoting tall datasets into wide views, handling missing metric values, ordering ISO date strings via string operations, and meeting algorithmic efficiency constraints (O(n log n)).
Data Manipulation (SQL/Python)Onsite - InstacartMediumSoftware EngineerPivot order-status counts
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Pivot order-status counts states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - InstacartMediumSoftware EngineerPivot transactions by date without date libs
This question evaluates proficiency in data manipulation, string-based date handling, aggregation and pivot transformations, along with reasoning about data structures, de-duplication and missing-value filling.
Data Manipulation (SQL/Python)Onsite - InstacartMediumSoftware EngineerReserve Cart Inventory Without Overselling
Design a high-throughput inventory reservation system that locks stock when items are added to a cart, prevents overselling during flash promotions, handles automatic reservation expiration, and scales seamlessly under a 10x traffic spike.
System DesignOnsitesystem-designdistributed-systemsconcurrency - InstacartMediumSoftware EngineerResolve a Variable Through Literal and Reference Assignments
Resolve a target variable through an acyclic chain of named assignments until reaching an integer literal, independent of definition order.
Coding & AlgorithmsOnsite - InstacartMediumSoftware EngineerSenior Behavioral Round: Project Deep Dive, Mentoring, Trade-offs and Disagreement
A senior-level behavioral round covering four themes: a project deep dive, mentoring another engineer, a significant technical trade-off, and a disagreement with a colleague or manager. It tests ownership, depth on decisions, influence without authority and honest reflection on outcomes.
Behavioral & LeadershipOnsite - InstacartMediumSoftware EngineerShopping Cart Totals with Best-Offer Discounts and Aisle Ordering, Frozen Items Last
A practical coding exercise that parses shopping-cart item records and reports the total item count and price, then adds percentage discounts and buy-N-get-M-free offers, applying the cheapest offer per product. A final part orders items by aisle with frozen items last, testing parsing, exact money arithmetic and extensible code.
Software Engineering FundamentalsTechnical Screen - InstacartMediumSoftware EngineerSimulate bus boarding with priority and wheelchairs
This question evaluates queue and priority handling, stable ordering, capacity accounting, constraint handling for wheelchair riders, and the ability to design unit tests and articulate trade-offs within the Software Engineering Fundamentals category.
Software Engineering FundamentalsTechnical Screen - InstacartMediumSoftware EngineerSolve bank, password, expression algorithm tasks
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Solve bank, password, expression algorithm tasks states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - InstacartMediumSoftware EngineerSolve expression evaluator and string decoder
This question evaluates a candidate's ability in parsing, expression evaluation, and nested string decoding, including handling malformed input, character encoding nuances, and large-file streaming considerations.
Coding & AlgorithmsOnsite - InstacartMediumSoftware EngineerSpecify the Lowest Price Across Percentage and Buy-X-Get-Y Discounts
Clarify percentage and buy-x-get-y pricing rules, then reason about the cheapest legal discount combination, quantity thresholds, interactions, and rounding.
Software Engineering FundamentalsOnsite - InstacartHardSoftware EngineerTroubleshoot a production incident end-to-end
Troubleshoot a production incident end-to-end 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 DesignOnsite - Interactive BrokersMediumSoftware EngineerCalculate Tax Under Progressive Income Brackets
This problem tests the ability to iterate through sorted intervals and calculate values based on overlapping ranges, requiring careful boundary handling.
Coding & AlgorithmsOnline AssessmentArraysSimulationGreedy - Interactive BrokersEasySoftware EngineerCalculate Tax in a Progressive Marginal Tax System
Practice a Interactive Brokers coding interview problem focused on calculate tax in a progressive marginal tax system. The prompt emphasizes edge cases, clean implementation, and verifiable test behavior without revealing the solution.
Coding & AlgorithmsOnline Assessment - Intercontinental ExchangeMediumSoftware EngineerExplain Vector, Linked List, and Polymorphism
This question evaluates competency in C++ data structures and object-oriented polymorphism, testing understanding of dynamic array versus linked-list memory layouts, random access and insertion/deletion performance, cache locality, iterator invalidation, typical use cases, and distinctions between compile-time and runtime polymorphism including overloading, templates, inheritance, and virtual functions. It is commonly asked in software engineering fundamentals interviews to assess reasoning about performance and design trade-offs in C++ systems code; the domain is C++ programming, data structures, and OOP, and the level of abstraction spans both conceptual understanding and practical application.
Software Engineering FundamentalsTechnical Screen - IntersystemsEasySoftware EngineerFind the longest palindromic substring
This question evaluates string manipulation and algorithmic problem-solving skills, focusing on identifying palindromic substrings and reasoning about performance and edge cases. Commonly asked in the Coding & Algorithms domain to assess practical algorithmic application, it gauges understanding of time/space complexity, input constraints, and robustness in implementation.
Coding & AlgorithmsTechnical Screen - IntersystemsMediumSoftware EngineerMeasure 45 minutes with two ropes
This problem tests creative logical reasoning and the ability to decompose time-based tasks into parallelizable components without standard measurement tools.
Coding & AlgorithmsTechnical ScreenLogicPuzzlesAlgorithms - IntersystemsMediumSoftware EngineerParse nested XML inside CDATA
This problem tests your ability to safely extract, parse, and validate nested XML structures embedded within CDATA sections while addressing common parsing pitfalls.
Software Engineering FundamentalsTechnical ScreenXMLParsingSecurity - IntersystemsMediumSoftware EngineerPredict output when iterating ordered keys
This problem tests your understanding of ordered map iteration, the impact of modifying collection traversal, and handling accumulation logic in a state-dependent loop.
Coding & AlgorithmsTechnical ScreenData StructuresAlgorithmsIteration - IntersystemsEasySoftware EngineerTeach a networking concept to a beginner
This question evaluates a candidate's ability to teach and explain a networking concept, combining networking subject-matter knowledge with communication, mentorship, and leadership competencies.
Behavioral & LeadershipTechnical Screen - IntuitEasySoftware EngineerAdd One to Digit Array
This problem tests your ability to handle array-based arithmetic and carry-over logic, specifically focusing on edge cases like digit overflow and resizing the array.
Coding & AlgorithmsTechnical ScreenArrayMathSimulation - IntuitMediumSoftware EngineerAdd an LLM-backed recommendation API to an existing service with RAG and prompting
Add an LLM-powered recommendation endpoint to an existing backend service. Design the request flow, write the actual prompt and its structured output format, and discuss retrieval-augmented generation, hallucination, prompt injection, and how to evaluate and monitor the feature.
ML System DesignOnsite - IntuitMediumSoftware EngineerAggregate transactions by status and failure reasons (SQL)
This question evaluates a candidate's proficiency with SQL aggregation, grouping, window functions, string aggregation, and normalization techniques for summarizing transactional records by status and failure reasons.
Software Engineering FundamentalsOnline Assessment
Instacart
Intuit