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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.
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Showing 1471–1500 of 2336 results
- MicrosoftHardSoftware EngineerImplement idempotent request handling with idempotency keys
This problem tests your ability to design a thread-safe idempotency layer that ensures an API endpoint processes identical requests exactly once, even in the presence of concurrent execution.
Coding & AlgorithmsOnsiteConcurrencySynchronizationSystem Design - MicrosoftMediumSoftware EngineerImplement the Linux cp Command, Then Explain Its OS and C++ Internals
A low-level engineering exercise to implement the Linux cp command in C++ and then explain what happens beneath it. It tests system calls, short writes and error handling, the page cache and kernel-assisted copying, and RAII-based management of file descriptors.
Software Engineering FundamentalsOnsite - MicrosoftMediumSoftware EngineerImplement tree traversals, BFS, and subsets generation
This question evaluates proficiency with fundamental data structures and algorithms—binary tree traversals (preorder, inorder, postorder), breadth-first search on unweighted graphs, and power-set/subset generation—emphasizing implementation choices between recursive and iterative approaches and required time and space complexity reasoning.
Coding & AlgorithmsOnsite - MicrosoftMediumSoftware EngineerKeep Stable Unique Column Names Across Schema Changes
Maintain stable case-insensitive unique column names across additions, removals, reordering, reappearance, and natural suffix collisions, with independent table histories.
Coding & AlgorithmsOnsite - MicrosoftMediumSoftware EngineerLongest Single-Letter Substring After at Most k Letter Replacements
A string problem: given uppercase letters and a budget of k single-letter changes, find the longest contiguous substring that can be turned into one repeated letter. It tests efficient substring scanning with letter counts and careful reasoning about when a candidate substring stays valid.
Coding & AlgorithmsOnsite - MicrosoftMediumSoftware EngineerMaximize Equal Array Length After Contiguous Sum Merges
Determine the maximum possible length of two identical arrays formed by repeatedly merging adjacent elements of two given positive-integer arrays, or return -1 if impossible.
Coding & AlgorithmsOnsiteTwo PointersGreedyArrays - MicrosoftMediumSoftware EngineerMaximize profit with bounded sell window
This question evaluates proficiency in array algorithms, time and space complexity analysis, and techniques for bounded-range optimization and streaming adaptation.
Coding & AlgorithmsOnsite - MicrosoftEasySoftware EngineerMeasure Every Lake on a Map Tile, Listed in Scan Order
Compute the area of every water body on a rectangular map tile, reported in the order a row-by-row scan first touches each one; tests connected components on a grid and avoiding recursion limits on huge regions.
Coding & AlgorithmsOnsitegridgraph-traversaldfs - MicrosoftMediumSoftware EngineerMedian of Every Fixed-Length Sliding Window in an Integer Array
A coding problem that slides a window of fixed length k across an integer array and asks for the median of every window position, returned as floats in window order. It tests keeping the middle of a changing collection available as elements enter and leave, exact handling of even-sized windows, and overflow-safe averaging.
Coding & AlgorithmsOnsite - MicrosoftMediumSoftware EngineerMerge multiple sorted arrays using min-heap
This question evaluates algorithm design and data structure proficiency, focusing on merging multiple sorted sequences and reasoning about time and space complexity for large numbers of arrays and elements.
Coding & AlgorithmsOnsite - MicrosoftMediumSoftware EngineerMinimize Fuel Cost Across Cities
Calculate the minimum monetary cost to travel between two cities in a road network where fuel is consumed per unit distance and can be stockpiled with unlimited capacity at local city prices.
Coding & AlgorithmsOnsiteGraphDijkstraShortest Path - MicrosoftMediumSoftware EngineerMinimum Number of Rooms to Host Overlapping Meetings
A scheduling problem that asks for the fewest rooms needed to hold a set of meetings given as half-open time intervals, where a room freed at a given moment can be reused immediately. It tests interval reasoning, correct handling of shared endpoints and duplicates, and an efficient solution for large inputs.
Coding & AlgorithmsOnsite - MicrosoftMediumSoftware EngineerMinimum Ship Capacity to Deliver Ordered Packages Within a Day Limit
Given package weights in a fixed loading order and a number of days, find the smallest ship capacity that delivers every package within that many days, carrying one contiguous run of packages per day. It tests reasoning precisely about feasibility, choosing correct bounds and handling large inputs efficiently.
Coding & AlgorithmsOnsite - MicrosoftMediumSoftware EngineerPeer-to-Peer File Distribution: Discovery, Chunked Transfer and Integrity Checks
A system design interview question asking you to build a peer-to-peer file sharing network where users download large files directly from other users. It tests content identification, peer discovery, chunked parallel transfer with integrity checks, NAT traversal, incentives against free-riders, and keeping files available as peers churn.
System DesignOnsite - MicrosoftMediumSoftware EngineerPopulate next pointers in a perfect binary tree
Evaluates proficiency in tree traversal and in-place pointer manipulation, emphasizing the perfect binary tree invariant and space-time trade-offs; category/domain: Coding & Algorithms. It is commonly asked because it tests ability to perform level-wise linking under an O(1) extra-space constraint and operates at the implementation-level of algorithms and data structures.
Coding & AlgorithmsOnsite - MicrosoftMediumSoftware EngineerRecover Sorted Digits from Scrambled English Number Words
Recover sorted digits from scrambled English number-word letters, including repeats, and analyze why arbitrary customer vocabularies may lose unique recoverability.
Coding & AlgorithmsOnsite - MicrosoftMediumSoftware EngineerResolve Technical Disagreement and Work Across Different Styles
Discuss technical disagreement and contrasting work styles with fair alternatives, shared evidence, explicit decisions, and practical collaboration changes.
Behavioral & LeadershipOnsite - MicrosoftMediumSoftware EngineerRespond to a Reliability Regression Shortly After Deployment
Respond to a post-deployment latency or reliability regression with scoped diagnosis, safe rollback decisions, customer-impact measurement, and prevention.
Software Engineering FundamentalsOnsite - MicrosoftMediumSoftware EngineerResume Deep Dive: Technical Decisions, Personal Contribution, Challenges, Impact
A resume-driven behavioral interview that walks through a past project in depth: the architecture and technical decisions, what the candidate personally contributed, the hardest challenges, and the measurable impact. It tests ownership, technical judgment and clear, structured storytelling.
Behavioral & LeadershipOnsite - MicrosoftMediumSoftware EngineerReverse linked list in fixed-size groups
This question evaluates proficiency with singly linked list manipulation, pointer/reference management, in-place group operations, and complexity reasoning including time and constant extra space.
Coding & AlgorithmsOnsite - MicrosoftMediumSoftware EngineerRotate a 3×3 digit grid by 180°
This problem tests your ability to perform spatial transformations on a fixed-size 2D structure while maintaining data integrity across a transformation.
Coding & AlgorithmsOnsiteArraysMatrixStrings - MicrosoftHardSoftware EngineerShard a Large Input Embedding Table Across Devices
Compare vocabulary and hidden-dimension embedding sharding through per-rank storage, token routing, hidden-state layout, skew, and downstream communication.
ML System DesignOnsite - MicrosoftHardSoftware EngineerShard an LM Head and Combine Distributed Logits
Shard an LM head by vocabulary or hidden width, distinguishing complete logits from partial dot products and exact distributed top-k from full-distribution sampling.
ML System DesignOnsite - MicrosoftMediumSoftware EngineerSimulate a Throttled Function Wrapper That Keeps Only the Latest Pending Call
A coding simulation of a throttle wrapper: given a cooldown length and sorted call times, report which calls actually run and when, where calls arriving during a cooldown keep only the latest one pending. It tests precise event ordering, an explicit rule for calls at the exact moment a cooldown ends, and an efficient single pass.
Coding & AlgorithmsOnsite - MicrosoftEasySoftware EngineerSizes of 4-Connected Foreground Regions in a Binary Image, in Scan Order
Given a binary image stored as a matrix of 0s and 1s, return the size of every region of horizontally or vertically connected foreground pixels, ordered by when each region is first reached in a top-to-bottom, left-to-right scan. It tests grid traversal, connected components, and handling a single region that covers up to a million pixels.
Coding & AlgorithmsOnsite - MicrosoftHardSoftware EngineerSolve Throughput, Rate Limiting, and LFU
This problem tests your ability to design a system with O(1) time complexity for cache operations and time-window-based request tracking.
Coding & AlgorithmsOnsiteData StructuresHashingSliding Window - MicrosoftHardSoftware EngineerSolve cache, grid path, and substring problems
This problem tests your ability to implement an LRU cache, solve a dynamic programming problem on a grid with constraints, and optimize string searching using the sliding window technique.
Coding & AlgorithmsOnsiteHash MapLinked ListDynamic Programming - MicrosoftMediumSoftware EngineerSolve three scheduling and array problems
This multi-part question evaluates algorithmic problem-solving skills across task scheduling with cooldowns, in-place array deduplication, and string rearrangement to avoid adjacent duplicates, highlighting concepts such as frequency counting, scheduling constraints, and two-pointer or in-place techniques within the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - MicrosoftMediumSoftware EngineerThread Safety, Deadlock Prevention, and Arrays vs Linked Lists
A rapid-fire software engineering fundamentals round covering what makes code thread-safe, what a deadlock is, the main ways to prevent, avoid or recover from deadlocks, and how arrays and linked lists compare. It tests precise definitions, concrete examples and practical trade-offs such as lock ordering and cache locality.
Software Engineering FundamentalsOnsite - MicrosoftMediumSoftware EngineerTraverse a Matrix in Clockwise Spiral Order
Traverse a rectangular matrix in clockwise spiral order without modifying the input. Learn the four-boundary technique and the guards that prevent duplicate visits on the final row or column.
Coding & AlgorithmsOnsite
Microsoft