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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 2551–2580 of 2810 results
- TikTokEasySoftware EngineerFind start indices of anagram substrings
This question evaluates proficiency in string processing, frequency-based pattern matching, and algorithmic efficiency under length constraints, testing the ability to reason about time and space trade-offs for substring searches.
Coding & AlgorithmsTechnical Screen - TikTokMediumSoftware EngineerFind the Longest Substring with at Most Two Distinct Characters
Tests the ability to use the sliding window technique combined with a hash map to maintain a dynamic character set and determine the maximum length of a valid substring in linear time.
Coding & AlgorithmsTechnical Screensliding-windowhash-tabletwo-pointers - TikTokMediumSoftware EngineerFlatten object & Promise.all
This question evaluates proficiency in JavaScript data manipulation and asynchronous programming, testing competencies in transforming nested objects into single-level key paths and reproducing Promise.all semantics.
Coding & AlgorithmsTechnical Screen - TikTokEasySoftware EngineerGive a Technical Research-Project Deep Dive
Tests your ability to communicate complex technical research clearly, delineate your specific personal contributions, explain rigorous experimental design, and critically evaluate limitations and next steps.
Behavioral & LeadershipTechnical ScreenResearchTechnical Deep DiveProject Walkthrough - TikTokMediumSoftware EngineerHandle disorganized interview logistics
This question evaluates a candidate's communication, initiative, and stakeholder-management competencies in coordinating interview logistics for a Software Engineer role.
Behavioral & LeadershipTechnical Screen - TikTokMediumSoftware EngineerImplement O(1) randomized multiset
Implement O(1) randomized multiset 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 - TikTokMediumSoftware EngineerImplement a match-3 board resolver
TikTok software-engineer technical-screen coding question: implement a match-3 board resolver over an m×n grid. Repeatedly remove connected horizontal/vertical runs of three or more equal cells, apply gravity so survivors fall and blanks rise to the top, cascade until the board is stable, and return the final board plus the total cells removed. It tests grid simulation, run detection via linear scans, per-column gravity, termination reasoning, and time/space complexity analysis.
Coding & AlgorithmsTechnical Screen - TikTokEasySoftware EngineerImplement an LRU cache
This question tests the ability to implement a Least Recently Used (LRU) cache using a combination of a hash map and a doubly linked list to achieve constant time complexity for core operations.
Coding & AlgorithmsTechnical ScreenHash MapLinked ListDesign - TikTokMediumSoftware EngineerImplement and compare key design patterns
Implement and compare key design patterns evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Software Engineering FundamentalsTechnical Screen - TikTokMediumSoftware EngineerImplement binary tree in-order traversal
This question evaluates understanding of binary tree traversal, comparing recursive and iterative (explicit stack) implementations and their time and space complexity. Commonly asked in Coding & Algorithms interviews to assess both practical implementation and conceptual understanding of tree data structures, algorithmic trade-offs, and complexity analysis.
Coding & AlgorithmsTechnical Screen - TikTokHardSoftware EngineerImprove and measure service performance
This question evaluates performance engineering and observability skills—specifically SLIs/SLOs definition, instrumentation and profiling, load-testing, bottleneck identification, and optimization trade-offs for stateless HTTP microservices.
System DesignTechnical Screen - TikTokMediumSoftware EngineerIntroduce yourself and explain your project
This question evaluates communication, ownership, leadership, and impact articulation by prompting a personal introduction and a focused project narrative covering business context, responsibilities, delivered features, and key challenges.
Behavioral & LeadershipTechnical Screen - TikTokEasySoftware EngineerInvestigate an iOS Memory Failure
Tests understanding of iOS memory management fundamentals, including differentiating Jetsam OOM events from fatal access exceptions, pinpointing retain cycles and memory growth, and using Xcode profiling tools to confirm fixes.
Software Engineering FundamentalsTechnical ScreeniOSSwiftMemory Management - TikTokMediumSoftware EngineerMaximize min+max of contiguous subarray
This question evaluates understanding of array algorithms and competency in identifying and reasoning about minimum and maximum values within contiguous subarrays, emphasizing extremal value handling.
Coding & AlgorithmsTechnical Screen - TikTokMediumSoftware EngineerParse a nested list from a string
This problem tests your ability to parse recursive nested structures using stack-based iteration or recursion and string manipulation.
Coding & AlgorithmsTechnical ScreenRecursionStackParsing - TikTokMediumSoftware EngineerParse chemical formula with multipliers
Parse chemical formula with multipliers 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 - TikTokEasySoftware EngineerPlan QA testing for a new feature
This problem tests your ability to structure a comprehensive quality assurance strategy for a social media feature, balancing functional testing, edge cases, and automation.
Software Engineering FundamentalsTechnical ScreenQATesting StrategySystem Design - TikTokMediumSoftware EngineerReconstruct a tree from two traversals
Reconstruct a tree from two traversals 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 - TikTokMediumSoftware EngineerRestore Every Valid IP Address
Implement a backtracking algorithm to partition a digit string into four valid IPv4 octets, adhering to numerical range and leading-zero constraints.
Coding & AlgorithmsTechnical ScreenBacktrackingStringRecursion - TikTokMediumSoftware EngineerSolve array and tree algorithm challenges
This question evaluates algorithmic problem-solving skills across array, heap, and tree data structures, testing competencies in duplicate handling, frequency aggregation, and balancing root-to-leaf path sums within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - TikTokMediumSoftware EngineerSolve common string/DP/stack problems
This problem tests your ability to identify and implement an efficient solution for finding the longest substring that satisfies specific constraints, requiring a sliding window approach.
Coding & AlgorithmsTechnical ScreenSliding WindowHash MapStrings - TikTokHardSoftware EngineerSolve four OA algorithm problems
This problem tests your ability to optimize string manipulation using greedy approaches and Fenwick trees to count minimum adjacent swaps required to transform a string into a palindrome.
Coding & AlgorithmsTechnical ScreenGreedyStringsTwo Pointers - TikTokMediumSoftware EngineerSolve linked list, string filtering, and puzzle
This problem tests your ability to manipulate linked list pointers in-place, apply conditional string filtering with index tracking, and solve a greedy resource partitioning puzzle.
Coding & AlgorithmsTechnical ScreenLinked ListStringsGreedy - TikTokMediumSoftware EngineerSolve message splitting and board crushing
These problems evaluate string manipulation and numeric reasoning for variable-length metadata alongside grid simulation with pattern detection and gravity effects, testing skills such as careful edge-case handling, iterative state updates, and complexity analysis.
Coding & AlgorithmsTechnical Screen - TikTokMediumSoftware EngineerSolve three algorithm tasks
This multi-part question evaluates algorithmic problem-solving across string processing (text justification), handling ambiguous state in sequence validation (parentheses with wildcards), and grid graph traversal with path reconstruction, testing competencies in formatting and spacing logic, state-tracking for correctness under uncertainty, and shortest-path search and reconstruction. It is commonly asked in Coding & Algorithms interviews to assess correctness under edge cases, ability to reason about trade-offs and invariants, and the analysis of time and space complexity, requiring both conceptual understanding and practical implementation skills.
Coding & AlgorithmsTechnical Screen - TikTokHardSoftware EngineerSolve three string/stack/backtracking problems
This problem tests your ability to use a monotonic stack to determine visibility in a 2D line and backtracking to generate valid structural sequences.
Coding & AlgorithmsTechnical ScreenMonotonic StackBacktrackingRecursion - TikTokMediumSoftware EngineerSolve top-K and string rotation match
Solve top-K and string rotation match 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 - TikTokEasySoftware EngineerTrace Source Code to an Executable
This question tests the candidate's understanding of the C/C++ compilation pipeline, focusing on how source code is transformed into a runnable binary and the role of different build artifacts.
Software Engineering FundamentalsTechnical ScreenCompilationLinkingToolchain - TikTokMediumSoftware EngineerWalk through resume and resolve conflicts
Walk through resume and resolve conflicts 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 - TikTokMediumSoftware EngineerWrite complex SQL for cohorts and retention
This question evaluates advanced SQL and data-engineering competencies such as cohort and retention analysis, deduplication, timezone normalization, last-touch attribution, aggregate revenue calculations, and effective use of window functions in the Data Manipulation (SQL/Python) domain.
Data Manipulation (SQL/Python)Technical Screen
TikTok