practice a little every day, paws crossed ♡
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 1321–1350 of 9403 results
- AppleMediumMachine Learning EngineerImplement permutations and image retrieval
This question evaluates algorithmic implementation and computational thinking across combinatorics, image processing, and vector similarity—specifically testing permutation generation, 2D convolution with explicit boundary handling, and nearest-neighbor retrieval for image embeddings.
Coding & AlgorithmsOnsite - AppleHardData ScientistImplement random forest with OOB and imbalance
This question evaluates expertise in implementing and engineering a memory- and compute-efficient Random Forest for binary classification, covering ensemble methods, CART/Gini impurity, OOB evaluation and calibration, class-imbalance handling, reproducibility, parallel and thread-safe system design, and streaming/warm-start model updates.
Machine LearningOnsite - AppleMediumSoftware EngineerImplement rotation, LRU cache, streaming median, cycle detection
This question evaluates understanding of array/matrix manipulation, cache and data structure design, streaming algorithms for median maintenance, and graph theory for cycle detection, with emphasis on algorithmic complexity analysis and handling of edge cases.
Coding & AlgorithmsOnsite - AppleMediumAccessories Software QA EngineerImprove QA Benchmarks, Regression Tests, and HPC Resource Use
Explain functional regression testing, reproducible performance benchmarks, and how to reduce shared HPC resource use without weakening test coverage.
Software Engineering FundamentalsOnsite - AppleMediumSoftware EngineerImprove chip performance without process advances
This question evaluates understanding of digital architecture, microarchitecture, and logic‑level techniques for improving chip performance without process advances, along with competence in performance/power/area (PPA) trade‑off analysis and arithmetic block design.
Software Engineering FundamentalsTechnical Screen - AppleMediumSoftware EngineerIntroduce yourself and align with team focus
This question evaluates a candidate's communication and leadership skills, ability to concisely summarize technical work, quantify individual contributions and impacts, and domain knowledge in diffusion models and speech/multimodal research as part of a Behavioral & Leadership assessment for a Software Engineer role.
Behavioral & LeadershipTechnical Screen - AppleMediumSoftware EngineerLRU Cache with Fewer Recency Writes and Concurrent Access
Implement a fixed-capacity least-recently-used cache with constant-time get and put, then discuss two follow-ups: cutting the shared-state writes that every read causes when it updates recency, and making the cache safe and fast under concurrent access, including how eviction order changes.
Software Engineering FundamentalsOnsite - AppleHardSoftware EngineerMake tree iterators safe under concurrency
This question tests the ability to design a thread-safe iterator for a binary search tree (BST) that remains consistent even if the underlying tree structure is modified during iteration.
Software Engineering FundamentalsTechnical ScreenConcurrencyTreesIterators - AppleMediumSoftware EngineerMaximize funds with capital-gated projects
Maximize funds with capital-gated projects evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - AppleMediumSoftware EngineerMerge Two Strings Using the Longest Edge Overlap
Compare both suffix-to-prefix concatenation orders, merge the longest edge overlap, and favor the original string order when overlap lengths tie.
Coding & AlgorithmsOnline Assessment - AppleMediumSoftware EngineerMerge overlapping time intervals
This problem tests your ability to manipulate array-based data using sorting and linear scanning to identify and merge overlapping intervals.
Coding & AlgorithmsTechnical ScreenSortingIntervalsGreedy - AppleHardSoftware EngineerMigrate a monolithic wallet to microservices
This question evaluates a candidate's ability to design and plan a safe, compliant migration of a high-scale digital wallet from a monolithic architecture to microservices, covering service decomposition, data ownership, transactional consistency, security and key management, compliance, observability, and deployment strategies.
System DesignTechnical Screen - AppleHardSoftware EngineerMinimum Cells to Bridge a Magic Grid
Tests graph modeling and shortest-path optimization on a 2D grid with zero-weight transitions and unit-weight bridges using 0-1 BFS or Dijkstra's algorithm.
Coding & AlgorithmsTechnical ScreenGraph0-1 BFSMatrix - AppleMediumSoftware EngineerMultiply Two Sparse Matrices
This problem tests your ability to optimize matrix multiplication by leveraging data sparsity to avoid unnecessary computations and handle memory efficiently.
Coding & AlgorithmsTechnical ScreenArraysMatricesOptimization - AppleMediumSoftware EngineerObject-Oriented Design: Hotel Room Booking System
Tests object-oriented domain modeling, interval-overlap availability logic, and concurrency control strategies to prevent double bookings in a hotel reservation system.
System DesignOnsiteObject-Oriented DesignConcurrencyDatabase Design - AppleMediumSoftware EngineerOptimize QA Benchmarks and Shared HPC Usage
Optimize QA benchmark turnaround and shared HPC usage by profiling execution, controlling resources, and separating runtime savings from faster reporting.
Software Engineering FundamentalsOnsite - AppleMediumMachine Learning EngineerOptimize image filters on device
This question evaluates competency in on-device machine learning and performance engineering, covering algorithm choice, numerical precision trade-offs, hardware utilization (CPU/GPU/accelerator), memory layout, tiling/streaming, and trade-offs among latency, memory overhead, and battery impact.
ML System DesignOnsite - AppleEasySoftware EngineerParse and Summarize HTTP Access Logs
Parse a strict HTTP access-log format and summarize valid requests, client errors, server errors, invalid lines, and failure percentage. The prompt tests full-field validation, precise metric denominators, status boundaries, streaming aggregation, and privacy-safe diagnostics.
Software Engineering FundamentalsTechnical Screen - AppleMediumSoftware EngineerPin Down a Vague HTML Parser Prompt, Build the Element Tree, and Query It with DFS
A coding exercise in which the HTML parser prompt is deliberately vague, so the candidate must first pin down input, output and edge cases with concrete examples. It tests building a tree from nested markup in one pass, handling void and malformed tags, and answering a query with a depth-first traversal.
Software Engineering FundamentalsOnsite - AppleMediumSoftware EngineerProject Deep Dive: End-to-End Walkthrough, Trade-offs and Communicating Decisions
A behavioral deep dive on your own work rather than generic situational questions. You walk through a project end to end, then defend the trade-offs you made and the alternatives you rejected, explain how you communicated technical decisions to others, and reflect on what you would change.
Behavioral & LeadershipOnsite - AppleMediumSoftware EngineerRedesign an Existing Relational Database to Reduce Read Latency
A staff-level screen question about an existing service whose normalized relational database serves slow reads: explain how you would change the data model and read path to cut read latency. Tests diagnosis of slow reads, trade-offs between read cost, write cost and data freshness, and safe rollout on a live system.
System DesignTechnical Screen - AppleMediumSoftware EngineerReduce False Failures and Classify QA Outcomes
Reduce regression false failures with reviewed acceptance rules, then classify causes and severity without confusing test categories with observed outcomes.
Software Engineering FundamentalsOnsite - AppleMediumSoftware EngineerRefactor rock–paper–scissors for config and ties
This question evaluates a candidate's proficiency in object-oriented design, configuration injection, extensibility, state tracking (including ties), and testability when refactoring a Rock–Paper–Scissors tournament to support configurable rounds.
Coding & AlgorithmsOnsite - AppleMediumData ScientistRemove shortest subarray to sort array
This question evaluates proficiency in array algorithms, algorithmic efficiency (linear time and constant-space reasoning), and handling edge cases related to non-decreasing order, within the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - AppleMediumSoftware EngineerReturn the First Successful Result from Parallel API Calls Under a Global Timeout
Implement a function that runs several slow, failure-prone backend API calls concurrently and returns the first successful result within a single overall timeout. It tests concurrency primitives, deadline handling, reporting when every call fails, and cleaning up calls that are still in flight, using threads, futures, or async code.
Software Engineering FundamentalsTechnical Screen - AppleMediumSoftware EngineerRevisit a Technical Decision That Turned Out Wrong
This question assesses your self-awareness, integrity, and growth mindset by exploring how you handle professional mistakes and integrate those lessons into your engineering philosophy.
Behavioral & LeadershipOnsiteBehavioralLeadershipConflict Resolution - AppleMediumMachine Learning EngineerRotate a Matrix In Place
This question evaluates proficiency in in-place matrix and array manipulation, spatial data transformation, and reasoning about time and space complexity.
Coding & AlgorithmsTechnical Screen - AppleMediumSoftware EngineerScale Digit-Square Convergence Requests
This question evaluates a candidate's competency in designing scalable, low-latency distributed services that combine algorithmic optimization and caching to handle massive request volumes for a numerical convergence operation.
System DesignTechnical Screen - AppleMediumSoftware EngineerSimulate a Fixed-Capacity Least-Recently-Used Cache over a Stream of Operations
A coding question that asks you to implement a fixed-capacity key-value cache with least-recently-used eviction and run it over a stream of get and put operations. It tests precise recency and eviction rules, updates to keys already in the cache, and the design of a data structure with constant-time operations.
Coding & AlgorithmsTechnical Screen - AppleHardSoftware EngineerSmallest Valid Task Order from Dependency Pairs (Topological Sort)
Given a number of tasks and dependency pairs, return the lexicographically smallest order that completes every task while respecting all dependencies, or an empty list when a cycle makes that impossible. Tests topological sorting, cycle detection and deterministic tie-breaking on large dependency graphs.
Coding & AlgorithmsOnsite
Apple