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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
- Questions
- 546
- Companies
- 11
- Topics
- 8
- Languages
Showing 1201–1230 of 9403 results
- AppleMediumFrontend EngineerBuild an Accessible Recursive Expand-and-Collapse Tree in React
This problem tests recursive component design in React, state management for nested data structures, and the implementation of WAI-ARIA standards for accessible UI components.
Software Engineering FundamentalsTechnical ScreenReactFrontendAccessibility - AppleEasySoftware EngineerCafe Open-Now Check: Split Shifts and Midnight-Crossing Hours
Build an 'is the cafe open right now' check across three stages of growing complexity -- one fixed daily window, then select weekdays, then multiple shifts per day including windows that cross midnight. Tests clean incremental time modeling more than any single clever algorithm.
Software Engineering FundamentalsTechnical Screentimemodelingintervals - AppleMediumSoftware EngineerCapture Enclosed O Regions in an X/O Grid Using Union-Find Instead of Flood Fill
Given a grid of X and O cells, capture every region of edge-connected O cells that does not touch the border by turning it into X, using a disjoint-set (union-find) structure instead of flood fill. Tests union-find implementation, mapping grid cells to set indices and correct border handling.
Coding & AlgorithmsTechnical Screen - AppleMediumMachine Learning EngineerChoose File Storage Tiers Using Access Predictions
Design an end-to-end machine learning and decision system that predicts file access likelihood to automatically transition cloud-stored user files across storage tiers to minimize operational cost while meeting retrieval latency SLAs.
ML System DesignTechnical Screenml-system-designprobability-calibrationcloud-storage - AppleHardData ScientistChoose Optimal Network Retry Threshold
This question evaluates competence in statistical analysis, experimental design, and decision-making under trade-offs between playback reliability and battery or radio power consumption.
Analytics & ExperimentationOnsite - AppleMediumData ScientistClarify status, education, and multi-role strategy
This question evaluates a candidate's ability to document and communicate U.S. work authorization details, resolve resume inconsistencies, articulate multi-level role positioning, and demonstrate minicase availability and preparation—assessing attention to detail, clarity of communication, stakeholder coordination, and practical readiness for data-science interviews. Commonly asked in Behavioral & Leadership screens for Data Scientist roles to verify eligibility, alignment with role expectations, and logistical readiness, it tests both conceptual understanding of career-leveling and contingency planning and practical application of documentation, messaging, and time-management.
Behavioral & LeadershipHR Screen - AppleMediumSoftware EngineerCloud Provider Design for Provisioning Resources Through Terraform
A cloud infrastructure design question asking what a cloud provider must build so customers can create, update and destroy its resources with Terraform. It tests mapping the Terraform resource lifecycle to provider APIs, handling long-running operations and their status, idempotent retries, and drift detection.
System DesignTechnical Screen - AppleMediumMachine Learning EngineerCompare DCN v1 vs v2 and A/B test
This question tests your understanding of architectural improvements in Deep & Cross Networks (DCN) and your ability to design a rigorous A/B testing strategy for model deployment in a high-stakes production environment.
Machine LearningTechnical ScreenDeep LearningCTR PredictionRecommendation Systems - AppleMediumData ScientistCompare Normal and Poisson Distributions in Statistics
Evaluates statistical understanding of Normal and Poisson distributions for counts and continuous measurements. Strong answers compare support, parameters, use cases, Normal approximation conditions, and mean-variance derivations.
Statistics & MathTechnical Screen - AppleMediumData ScientistCompare Normal vs Poisson; test dispersion and approximate tails
This question evaluates a data scientist's competency in statistical inference for count data, covering MLE and asymptotic variance estimation, Wald confidence intervals, tests for equidispersion versus overdispersion, Normal approximation with continuity correction for Poisson tails, and model selection diagnostics.
Statistics & MathTechnical Screen - AppleMediumMachine Learning EngineerCompare audio preprocessing and training
This question evaluates understanding of audio data preprocessing and end-to-end model training, assessing competencies in feature representation choices, normalization, segmentation, augmentation, and pipeline orchestration within machine learning for audio.
Machine LearningTechnical Screen - AppleHardSoftware EngineerCompute conflicts and minimum meeting rooms
This question evaluates the ability to reason about interval overlaps and resource allocation, testing algorithmic thinking and efficient handling of time-interval data in scheduling contexts and belongs to the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - AppleMediumSoftware EngineerCompute island size in grid
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Compute island size in grid states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - AppleMediumSoftware EngineerCompute minimum required meeting rooms
This question evaluates understanding of interval scheduling and resource-allocation concepts, proficiency with data structures for detecting temporal overlaps (heap and sweep-line paradigms), and the ability to analyze time and space complexity while handling edge cases.
Coding & AlgorithmsTechnical Screen - AppleHardData ScientistCompute optimal matrix-chain multiplication order
This question evaluates dynamic programming, algorithmic analysis, and sensitivity reasoning for matrix-chain multiplication, and it belongs to the Coding & Algorithms domain; it is commonly asked because it tests understanding of optimal substructure, trade-offs in parenthesization, and correctness versus greedy heuristics.
Coding & AlgorithmsOnsite - AppleMediumSoftware EngineerCompute top three scores per student
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Compute top three scores per student states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - AppleMediumData ScientistConstruct a Churn-Prediction Pipeline Using Scikit-Learn
This question tests practical machine learning engineering skills, specifically the ability to construct an end-to-end classification pipeline for imbalanced tabular data. It evaluates knowledge of preprocessing, model validation, probability calibration, and production packaging — core competencies assessed in data scientist interviews.
Machine LearningTechnical Screen - AppleMediumSoftware EngineerConvert a Roman Numeral to an Integer
This problem tests your ability to parse string-based symbols while applying conditional arithmetic logic to handle additive and subtractive Roman numeral rules.
Coding & AlgorithmsOnsiteStringsHash MapMath - AppleMediumSoftware EngineerCopy a Linked List with Random Pointers
This problem tests your ability to manipulate linked structures and manage pointer state without using extra hash maps for space optimization.
Coding & AlgorithmsOnsiteLinked ListPointer ManipulationAlgorithms - AppleMediumSoftware EngineerCount Islands in a Binary Grid
This problem tests your ability to perform graph traversal on a 2D grid while adhering to strict memory constraints and preserving the integrity of the original data structure.
Coding & AlgorithmsTechnical ScreenGraphsBFSIterative Traversal - AppleHardSoftware EngineerCount subarrays with sum equals k
This problem tests your ability to optimize subarray sum calculations using prefix sums and hash maps to achieve linear time complexity.
Coding & AlgorithmsTechnical ScreenArraysHash MapPrefix Sum - AppleMediumSoftware EngineerCount the Nodes in a Chain Reachable Only Through Left and Right Links
Starting from one node of a chain in which every node links only to its left and right neighbors, count the nodes in the whole chain. It tests traversal in both directions from an arbitrary node, handling of chain ends and single-node chains, and the design of your own test cases.
Coding & AlgorithmsTechnical Screen - AppleMediumMachine Learning EngineerDebug a PyTorch U-Net shape mismatch
This question tests your ability to calculate the output dimensions of convolutional layers in a U-Net architecture and resolve shape mismatches caused by cropping or padding requirements during feature map concatenation.
Coding & AlgorithmsTechnical ScreenPyTorchComputer VisionU-Net - AppleMediumSoftware EngineerDecode a Run-Length Encoded String Where a Missing Count Means One
Implement a decoder for run-length encoded strings in which each lowercase letter is followed by an optional repeat count, so that a5b3c becomes aaaaabbbc. It tests careful string parsing, multi-digit counts, letters written without a count, and writing your own test cases.
Coding & AlgorithmsTechnical Screen - AppleMediumSoftware EngineerDescribe End-to-End Ownership of a Project
This question assesses a candidate's ability to demonstrate end-to-end technical ownership, cross-functional collaboration, and the capacity to learn from post-launch challenges.
Behavioral & LeadershipOnsiteLeadershipProject OwnershipSoft Skills - AppleMediumData ScientistDescribe Your Role in a Recent Successful Project
This interview question evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer for Describe Your Role in a Recent Successful Project states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Behavioral & LeadershipTechnical Screen - AppleMediumSoftware EngineerDescribe common RTL lint warnings and errors
This question evaluates understanding of RTL static analysis and common lint warnings/errors in Verilog/SystemVerilog, testing competence in diagnosing issues such as modules treated as black boxes, combinational loops, and width mismatches.
Software Engineering FundamentalsTechnical Screen - AppleMediumMachine Learning EngineerDescribe recent project experiences
Describe recent project experiences 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 - AppleMediumSoftware EngineerDescribe your most memorable bug and fix
Evaluates debugging, root-cause analysis, incident response, communication, and ownership skills for a Software Engineer within the Behavioral & Leadership domain.
Behavioral & LeadershipTechnical Screen - AppleMediumSoftware EngineerDescribe your recent project and scope
Describe your recent project and scope 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
Apple