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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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Showing 6691–6720 of 9403 results
- OtherEasySoftware EngineerValidate Nested Parentheses, Brackets, and Braces
Validate nested parentheses, brackets, and braces with correct handling of empty input, mismatched closing symbols, and unfinished groups.
Coding & AlgorithmsOnline Assessment - OtherMediumData ScientistWrite SQL to analyze response accuracy and speed
This question evaluates proficiency with SQL-based data manipulation and analytical querying on relational assessment data, including aggregation, grouping, joins, windowed ranking, and use of PostgreSQL statistical functions to analyze accuracy and response-time metrics.
Data Manipulation (SQL/Python)Online Assessment - OtherMediumData ScientistWrite mini-batch gradient descent
This question evaluates understanding and implementation of optimization algorithms for machine learning, specifically mini-batch gradient descent, and measures competency in numerical optimization, algorithmic implementation, and training dynamics within the Coding & Algorithms domain for Data Scientist roles.
Coding & AlgorithmsOnsite - OthersEasyData ScientistAnswer ancestor-walk queries on a rooted tree
This question evaluates understanding of tree data structures and ancestor-walk queries, assessing competency in traversing rooted trees, interpreting parent arrays, and designing efficient query-processing methods for large n and q.
Coding & AlgorithmsOnline Assessment - OthersMediumSoftware EngineerAnswer k-step ancestor queries in a rooted tree
This problem tests your ability to optimize ancestor lookups in a tree using the Binary Lifting technique to achieve logarithmic query time.
Coding & AlgorithmsOnline AssessmentTreesBinary LiftingDynamic Programming - OthersEasyData ScientistCompute per-coin quarterly amounts and totals
This question evaluates competence in SQL data manipulation—specifically time-based conditional aggregation, grouping, joins, and handling entities with no activity—to compute per-coin quarterly sums and year-to-date totals.
Data Manipulation (SQL/Python)Online Assessment - OthersMediumSoftware EngineerWrite a quarterly SQL report and a bash max-file script
This problem tests your ability to perform conditional aggregation in SQL for time-series reporting and your proficiency in recursive shell scripting for system administration tasks.
Software Engineering FundamentalsOnline AssessmentSQLBashData Aggregation - Otter.AiMediumData EngineerDefend a Data Pipeline Architecture and Its Trade-offs
Prepare to defend a production data pipeline you genuinely built or changed. The prompt tests how you connect requirements to architecture, compare alternatives, explain replay and backfills, diagnose a hard failure, quantify outcomes, and reflect on ownership and trade-offs.
System DesignTechnical Screen - Otter.AiMediumSoftware EngineerDesign a Fault-Tolerant Meeting Bot Allocation System
Design the infrastructure between a web UI and a bot pool. Connect requirements and APIs to data modeling, consistency, scaling, failure recovery, observability, and the important design trade-offs.
System DesignOnsite - Otter.AiMediumSoftware EngineerDesign a Google Docs-Style Real-Time Collaborative Editing Backend
Design the backend of a Google Docs-style editor in which many users edit the same document in real time and every copy converges to the same text. Tests concurrency control for simultaneous edits, routing of document sessions, operation storage and revision history, presence, and recovery from disconnects and server failures.
System DesignOnsite - Otter.AiMediumSoftware EngineerEvaluate 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 EngineerExtend 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 EngineerFewest Adjacent-GCD Operations to Turn Every Array Element into 1
Given an array of positive integers, find the fewest operations that make every element 1, where each operation replaces one of two neighboring values with their greatest common divisor, or return -1 if it cannot be done. Tests GCD properties, lower-bound reasoning and careful case analysis on small arrays.
Coding & AlgorithmsOnsite - Otter.AiMediumData EngineerFind Every Project with the Most Employees
Build a PostgreSQL aggregation that returns every project tied for the largest employee count. This compact exercise checks grouping, maximum selection, tie preservation, empty-input behavior, and careful use of primary-key guarantees.
Data Manipulation (SQL/Python)Technical Screen - Otter.AiMediumData EngineerFind the Highest-Paid Employee in Each Department
Work through a tie-aware PostgreSQL problem that finds every highest-paid employee in each department. It assesses relational reasoning, correct joins, duplicate-name handling, and precise output semantics without assuming a single winner.
Data Manipulation (SQL/Python)Technical Screen - Otter.AiMediumSoftware EngineerFixed-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 EngineerImplement 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 EngineerIn-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 EngineerValidate 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 - OuraMediumSoftware EngineerImplement Server Number Allocation
This problem tests your ability to manage and reuse resources efficiently using data structures that allow for logarithmic time allocation and deallocation within partitioned namespaces.
Coding & AlgorithmsOnline AssessmentData StructuresHeapHash Map - PDT PartnersMediumMachine Learning EngineerList All Positive Divisors of an Integer in Ascending Order, Then Beat Square-Root Time
Given a positive integer up to one trillion, return every positive divisor in ascending order, each listed once. The task tests divisor enumeration, correct handling of perfect squares and 64-bit values, and a follow-up asking whether the running time can grow more slowly than the square root of n.
Coding & AlgorithmsTechnical Screen - PDT PartnersMediumMachine Learning EngineerProject Deep Dive: Low-Latency LSTM Inference at Scale and the LSTM vs Transformer Choice
A project deep dive on a small LSTM model served for large-scale, latency-sensitive inference. The candidate must explain the deployment hardware, latency requirement and use case, how inference latency was reduced, why an LSTM was chosen over a Transformer, and whether that choice still holds today.
Machine LearningTechnical Screen - PalantirMediumSoftware EngineerApply Item Coupons with Exact Per-Item Cent Rounding
Implement a checkout calculation engine that applies item-specific coupons to cart lines using exact banker's rounding (round-half-to-even) per unit and returns the final cart total in integer cents.
Coding & AlgorithmsOnline AssessmentSimulationData StructuresMath - PalantirMediumSoftware EngineerDesign a Real-Time Collision Warning System for Drones in Shared Airspace
Design a system that ingests live telemetry from many drones sharing airspace and warns operators when two of them are predicted to come too close. It tests streaming ingestion, spatial partitioning, trajectory-based conflict prediction, alert delivery and reliability under the latency and safety demands of a real-time system.
System DesignOther - PalantirEasySoftware EngineerDesign a Server Metrics Monitor
This question evaluates knowledge of distributed system design, scheduling and orchestration, concurrency, fault tolerance, and observability in the context of large-scale metric collection.
System DesignOnsite - PalantirMediumSoftware EngineerDesign a Tool Registration, Discovery and Safe Execution Layer for LLM Agents
A senior system design question about the platform that lets LLM-driven agents discover and call backend tools. It probes tool registration and discovery, schema definition versus runtime validation of model-generated arguments, the interface between backend services and agents, and patterns for executing actions safely.
System DesignOther - PalantirMediumSoftware EngineerDesign a compliant multi-tenant analytics platform
This question tests the ability to design a secure, scalable multi-tenant analytics platform that enforces strict data isolation and fine-grained access control while maintaining rigorous audit trails.
System DesignOnsiteMulti-tenancySecurityABAC - PalantirHardSoftware EngineerDesign 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 EngineerDiscuss 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 - PalantirEasySoftware EngineerFind Shortest Paths in Road Network
This question evaluates understanding of graph data structures and shortest-path concepts, including correct modeling of undirected edges, unweighted versus weighted pathfinding, and algorithmic time and space complexity.
Coding & AlgorithmsOnsite
Otter.Ai
Palantir