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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 901–930 of 5874 results

  • AppleEasySoftware Engineer
    Implement flood fill using BFS and DFS

    This question tests the ability to implement graph traversal algorithms (BFS and DFS) on a 2D grid, focusing on boundary conditions and state management.

    Coding & AlgorithmsTechnical ScreenGraphBFSDFS
  • AppleMediumSoftware Engineer
    Implement 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
  • AppleMediumSoftware Engineer
    Improve 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 Engineer
    Introduce 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 Engineer
    LRU 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 Engineer
    Make 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 Engineer
    Maximize 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 Engineer
    Merge 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 Engineer
    Merge 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 Engineer
    Migrate 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 Engineer
    Minimum 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 Engineer
    Multiply 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 Engineer
    Object-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 Engineer
    Optimize 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
  • AppleEasySoftware Engineer
    Parse 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 Engineer
    Pin 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 Engineer
    Project 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 Engineer
    Redesign 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 Engineer
    Reduce 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 Engineer
    Refactor 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
  • AppleMediumSoftware Engineer
    Return 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 Engineer
    Revisit 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
  • AppleMediumSoftware Engineer
    Scale 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 Engineer
    Simulate 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 Engineer
    Smallest 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
  • AppleMediumSoftware Engineer
    Solve 15 common Apple coding questions

    This set evaluates algorithmic problem-solving and data-structure competence, including mastery of hash tables, linked lists, stacks, queues, heaps, graphs, sliding-window and two-pointer techniques, complexity analysis, and in-place transformations.

    Coding & AlgorithmsTechnical Screen
  • AppleMediumSoftware Engineer
    Solve 15 common interview problems

    This collection evaluates algorithmic problem-solving skills, mastery of fundamental data structures (arrays, strings, hash maps, stacks, queues, trees, graphs, linked lists) and the ability to reason about time and space complexity.

    Coding & AlgorithmsTechnical Screen
  • AppleMediumSoftware Engineer
    Solve Digit-Square and Grid BFS Problems

    This question evaluates understanding of digit-based state convergence and cycle detection alongside graph traversal and constrained shortest-path search, testing skills in number manipulation, state-space search, and BFS-style exploration.

    Coding & AlgorithmsTechnical Screen
  • AppleMediumSoftware Engineer
    Solve Subset Sum And Return All Matching Subsets

    This problem tests your ability to navigate the trade-off between dynamic programming and backtracking to find all unique combinations of elements that sum to a target value.

    Coding & AlgorithmsTechnical ScreenBacktrackingRecursionSorting
  • AppleMediumSoftware Engineer
    Solve interval, grid-fill, and heap tasks

    These combined tasks evaluate algorithmic problem-solving and data-structure design skills, specifically interval aggregation and counting over large timestamp ranges, constructive grid-filling with 4-directional connectivity constraints, and multiset operations supporting efficient retrieval and removal of minima and maxima.

    Coding & AlgorithmsTechnical Screen