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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
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- 11
- Topics
- 8
- Languages
Showing 2791–2810 of 2810 results
- eBayMediumSoftware EngineerFind the Longest Palindromic Substring
Implement an algorithm to find the longest palindromic substring in a given string, breaking ties by selecting the earliest occurrence and properly handling empty inputs.
Coding & AlgorithmsTechnical Screenstringstwo-pointersdynamic-programming - eBayMediumSoftware EngineerImplement list and grid transformation tasks
This problem tests your ability to simulate state-dependent transitions on a 2D grid and your skill in repartitioning data based on specific grouping constraints.
Coding & AlgorithmsTechnical ScreenArraysSimulationSorting - eBayEasySoftware EngineerLength of the Longest Contiguous Subarray Summing to a Target
Given an integer array that may contain negative numbers and a target k, return the length of the longest contiguous subarray whose sum equals k, or 0 when none exists. Tests reasoning about subarray sums with mixed signs and handling large inputs efficiently.
Coding & AlgorithmsTechnical Screen - eBayMediumSoftware EngineerRebuild a Binary Tree from Two Traversals and Serialize It Level by Level
Given the preorder and inorder traversals of a binary tree with distinct values, rebuild the tree and return its level-order serialization, with empty slots marked as None and trailing ones removed. It tests understanding of traversal orders, careful index bookkeeping and an efficient solution for trees with thousands of nodes, including fully skewed ones.
Coding & AlgorithmsTechnical Screen - eBayMediumSoftware EngineerReturn the K Smallest Values from Sorted Arrays
Tests ability to efficiently merge multiple sorted streams to extract the k smallest elements using a min-heap or frontier-based approach. Evaluates handling of empty arrays, duplicates, and computational complexity dependent on the number of arrays rather than total elements.
Coding & AlgorithmsTechnical ScreenHeapPriority QueueMerge Sort - eBayMediumSoftware EngineerSearch a Rotated Sorted Array in One Binary-Search Pass
Implement a single-pass binary search to locate a target value in a rotated strictly increasing array in logarithmic time and constant auxiliary space.
Coding & AlgorithmsTechnical Screenbinary-searcharraysdivide-and-conquer - eBayMediumSoftware EngineerWildcard Dictionary Matching
This problem tests your ability to implement a pattern-matching algorithm that supports variable-length wildcards using recursion with memoization or dynamic programming.
Coding & AlgorithmsTechnical ScreenRecursionDynamic ProgrammingString Matching - xAIMediumSoftware EngineerCompute dasher pay from order events
This question evaluates a candidate's ability to process time-based event streams, manage overlapping active intervals, and compute aggregate payouts under concurrency constraints.
Coding & AlgorithmsTechnical Screen - xAIMediumSoftware EngineerContrast processes and threads
This question evaluates understanding of operating system and concurrency fundamentals—specifically differences between processes and threads including memory isolation, resource ownership, scheduling, context-switch costs, inter-process communication versus in-process synchronization, failure isolation, and security.
Coding & AlgorithmsTechnical Screen - xAIMediumSoftware EngineerDesign a Durable Key-Value Cache with File-System Persistence
This question evaluates a candidate's ability to design durable in-memory data structures and persistence strategies, including reasoning about crash recovery, durability guarantees, and performance trade-offs.
System DesignTechnical Screen - xAIMediumSoftware EngineerDesign a Recoverable Iterator
Design a forward-only iterator wrapper that supports saving and restoring cursor state via checkpoints, testing buffering strategies and memory management.
Coding & AlgorithmsTechnical Screendesigndata-structuresiterators - xAIEasySoftware EngineerDesign a multi-level API rate limiter
This question assesses the ability to design a scalable, multi-tenant rate limiting service that supports hierarchical policies and global traffic coordination.
System DesignTechnical ScreenDistributed SystemsScalabilityCaching - xAIMediumSoftware EngineerExplain and Implement Strings
This question evaluates understanding of string data structures, memory layout, ownership and move semantics in Rust, and algorithmic complexity related to copying and performance.
Coding & AlgorithmsTechnical Screen - xAIMediumSoftware EngineerExplain arrays and memory layout
This question evaluates understanding of arrays, their contiguous memory representation including element size, alignment and indexing arithmetic, along with time-complexity analysis for access, insertion and deletion and implications for cache locality.
Coding & AlgorithmsTechnical Screen - xAIMediumSoftware EngineerExplain process vs thread and memory-sharing risks
This question tests the conceptual understanding of process versus thread architecture and the synchronization challenges inherent in shared-memory multithreading.
Software Engineering FundamentalsTechnical ScreenOperating SystemsConcurrencyMultithreading - xAIMediumSoftware EngineerExplain strings, moves, and concurrency
This question evaluates understanding of string data structures, ownership and move semantics (including Rust-specific move behavior), and concurrency models such as threads versus asynchronous coroutines, testing competencies in memory management, performance analysis, and concurrent programming.
Coding & AlgorithmsTechnical Screen - xAIHardSoftware EngineerFind kth element and sliding-window kth in stream
This problem tests your ability to maintain order statistics in a streaming context, moving from a static selection problem to an efficient sliding-window implementation.
Coding & AlgorithmsTechnical ScreenQuickSelectHeapSliding Window - xAIMediumSoftware EngineerFlatten and unflatten nested Python structures
This problem tests recursion, type introspection, and data structure manipulation by requiring the implementation of flattening and reconstruction logic for arbitrarily nested lists and dictionaries.
Coding & AlgorithmsTechnical ScreenRecursionData StructuresSerialization - xAIMediumSoftware EngineerImplement a Radix Cache for Integer Sequences
This question evaluates understanding of radix trees (prefix-compressed tries), sequence-oriented trie manipulation, and the maintenance of invariants like distinct branching and maximal compression, and belongs to the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - xAIHardSoftware EngineerMaximize distinct values after unique ± offsets
This problem tests greedy strategy and sorting to determine the maximum possible count of distinct values in an array after applying exactly one offset from a given set of allowed integers to each element.
Coding & AlgorithmsTechnical ScreenGreedySortingCombinatorics
xAI