Katkat

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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 2191–2220 of 4616 results

  • LinkedInHardSoftware Engineer
    Explain a Technical Project with an Architecture Diagram

    This question evaluates your ability to clearly explain a complex software architecture, articulate your personal technical ownership, justify design trade-offs, and quantify business and operational impact.

    Behavioral & LeadershipTechnical Screenbehavioralsystem architecturetechnical leadership
  • LinkedInMediumSoftware Engineer
    Explain a past project and critique a prior team

    This question evaluates communication of technical ownership, system architecture reasoning, and leadership competencies such as collaboration, conflict resolution, and influencing change within a Software Engineer role.

    Behavioral & LeadershipTechnical Screen
  • LinkedInMediumSoftware Engineer
    Explain database transactions and ACID

    This question evaluates a candidate's understanding of database transactions including ACID properties, isolation levels (read uncommitted, read committed, repeatable read, serializable), common anomalies (dirty reads, non-repeatable reads, phantom reads), MVCC, and commit/rollback semantics, testing competency in transactional correctness and concurrency control. Commonly asked in System Design and database contexts because it probes reasoning about data integrity, visibility, and durability under concurrent workloads, and it tests both conceptual understanding of transactional guarantees and practical application of isolation behavior in relational database systems.

    System DesignTechnical Screen
  • LinkedInMediumMachine Learning Engineer
    Explain gradient descent, learning rate, backpropagation, overfitting and batch size

    A machine learning fundamentals screen on how neural networks are trained: how gradient descent updates parameters, what the learning rate and batch size change, how backpropagation computes gradients, and how to diagnose and fix underfitting and overfitting. Tests mechanics and practical training judgment, not definitions alone.

    Machine LearningTechnical Screen
  • LinkedInEasyMachine Learning Engineer
    Explain overfitting vs underfitting and fixes

    This question tests the conceptual understanding of the bias-variance tradeoff and the practical strategies used to improve model generalization.

    Machine LearningTechnical ScreenModel EvaluationBias-Variance TradeoffRegularization
  • LinkedInMediumData Scientist
    Explain variance reduction in random forests

    This question tests your conceptual understanding of how Random Forests reduce the variance of base decision trees through bagging and feature randomness.

    Machine LearningTechnical ScreenEnsemble MethodsRandom ForestBias-Variance Trade-off
  • LinkedInEasySoftware Engineer
    Find dictionary words that match a phone keypad digit sequence

    Coding problem: given a list of known words and a digit string typed on a standard phone keypad, return every known word whose letters map to exactly that digit sequence, in sorted order. It tests string encoding, choosing a lookup structure for the dictionary, and analyzing time complexity.

    Coding & AlgorithmsTechnical Screen
  • LinkedInMediumData Scientist
    Find index with positive suffix sums

    This problem tests your ability to optimize array traversals using prefix or suffix sums, specifically evaluating your skill in calculating cumulative values efficiently in O(n) time.

    Coding & AlgorithmsTechnical ScreenArraysSuffix SumOptimization
  • LinkedInMediumMachine Learning Engineer
    Find shortest word transformation with caching

    Find shortest word transformation with caching 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
  • LinkedInMediumSoftware Engineer
    Find the Node Where Two Singly Linked Lists Merge

    Two singly linked lists stored in one successor array may merge at some node and share every node after it. Given both heads, return the first shared node, or -1 if the lists never meet. It tests linked-list traversal and careful handling of cases such as one list starting inside the other.

    Coding & AlgorithmsTechnical Screen
  • LinkedInMediumSoftware Engineer
    Generate All Distinct Permutations of a List with Duplicate Values

    Given a list of up to eight integers that may contain duplicates, return every distinct permutation exactly once, sorted in lexicographic order. It tests systematic enumeration, avoiding duplicate results caused by equal values, and producing a deterministic output order.

    Coding & AlgorithmsTechnical Screen
  • LinkedInEasyData Scientist
    Handle imbalance, validate samples, and avoid overfitting

    This question tests your ability to design a robust machine learning pipeline for a highly imbalanced classification task, focusing on sampling strategies, metric selection, and regularization techniques to prevent overfitting.

    Machine LearningTechnical ScreenImbalanceOverfittingRegularization
  • LinkedInEasyData Scientist
    How do you sample uniformly from an infinite stream?

    This question tests the implementation of Reservoir Sampling to maintain a uniform random sample of size k from a stream of unknown or infinite length.

    Coding & AlgorithmsTechnical ScreenAlgorithmsProbabilityStreaming
  • LinkedInMediumSoftware Engineer
    How do you win project buy-in?

    This question evaluates leadership, stakeholder management, and team resiliency competencies by probing experience in securing project buy-in and in preventing single-point-of-failure through knowledge sharing, documentation, and ownership distribution.

    Behavioral & LeadershipTechnical Screen
  • LinkedInMediumData Scientist
    How to analyze Simpson's paradox

    This question evaluates competency in causal reasoning, statistical inference, experimental design, and detection of Simpson's paradox within the Analytics & Experimentation domain.

    Analytics & ExperimentationTechnical Screen
  • LinkedInHardData Scientist
    How to diagnose traffic and measure relevance?

    This problem tests your ability to diagnose an unexplained drop in engagement metrics by decomposing a complex user funnel, isolating root causes using multidimensional data, and designing a robust validation framework.

    Analytics & ExperimentationTechnical ScreenRoot Cause AnalysisMetrics StrategyFunnel Analysis
  • LinkedInEasyData Scientist
    How would you lead a team to improve quality?

    This question evaluates leadership and technical execution competencies for a data scientist in a tech lead role, including work planning, delegation, accountability, stakeholder communication, root-cause diagnosis of product quality issues, metric definition, and delivering projects with measurable impact.

    Behavioral & LeadershipTechnical Screen
  • LinkedInMediumMachine Learning Engineer
    Implement K-Means and Explain Convergence

    This problem tests the implementation of the K-means clustering algorithm from scratch, requiring an understanding of the iterative refinement process, distance metrics, and the underlying mathematical objective.

    Coding & AlgorithmsTechnical ScreenClusteringUnsupervised LearningAlgorithms
  • LinkedInHardMachine Learning Engineer
    Implement a Text-Embedding Recommender Training Pipeline

    Tests the ability to structure an end-to-end, leakage-resistant training pipeline for a text-embedding recommender, covering profile flattening, embedding caching, temporal splits, binary classification, and artifact serialization.

    Machine LearningTechnical Screenrecommender-systemsfeature-engineeringnlp-embeddings
  • LinkedInMediumData Engineer
    Implement a stack supporting max and popMax

    This question evaluates understanding of data structures and algorithmic complexity, focusing on designing a stack variant that supports efficient retrieval and removal of the current maximum while preserving stack behavior.

    Coding & AlgorithmsTechnical Screen
  • LinkedInMediumData Scientist
    Implement fast sampling for weighted k-sided die

    This question evaluates understanding of probabilistic algorithm design, numerical stability, and efficient data-structure implementation for constant-time sampling from categorical distributions.

    Coding & AlgorithmsTechnical Screen
  • LinkedInMediumData Scientist
    Implement stream random sampling in Python

    This question evaluates understanding of streaming algorithms, uniform random sampling, and probabilistic guarantees for maintaining a fixed-size sample from an unbounded data stream (reservoir-sampling concepts).

    Coding & AlgorithmsTechnical Screen
  • LinkedInMediumSoftware Engineer
    Longest Run of Ones After One Flip

    This problem tests your ability to manage a sliding window with a flexible constraint, specifically counting zeros to determine the maximum length of a sequence after a single modification.

    Coding & AlgorithmsTechnical ScreenSliding WindowTwo PointersArray
  • LinkedInHardData Scientist
    Measure Relevant Feed Success

    This question tests the ability to define North Star metrics for a social feed and design an experimentation framework that accounts for long-term ecosystem health and cross-side network effects.

    Analytics & ExperimentationTechnical ScreenProduct AnalyticsA/B TestingMetrics
  • LinkedInEasySoftware Engineer
    Merge Two N-ary Trees by Matching Node Keys

    Merge two rooted n-ary trees in which every node has an integer key, combining nodes only when their keys match under matching parents. Tests recursive tree traversal, matching children by key, handling roots with different keys, and producing a canonical preorder encoding of the merged tree.

    Coding & AlgorithmsTechnical Screen
  • LinkedInHardSoftware Engineer
    Merge and Serialize N-ary Trees

    Tests recursive tree manipulation, immutable merging semantics, and robust string serialization/deserialization with input validation.

    Software Engineering FundamentalsTechnical Screentreerecursionparsing
  • LinkedInMediumSoftware Engineer
    Minimize adjacent-color assignment cost

    This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Minimize adjacent-color assignment cost states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Coding & AlgorithmsTechnical Screen
  • LinkedInEasySoftware Engineer
    Minimum index distance between two given words in a word list

    Coding problem: given a list of words and two different target words that both appear in it, return the smallest distance between an index of one word and an index of the other. It tests single-pass scanning with position tracking, handling of repeated occurrences, and time complexity analysis.

    Coding & AlgorithmsTechnical Screen
  • LinkedInMediumSoftware Engineer
    Randomized String Multiset With Average O(1) Insert, Remove and Weighted Random Pick

    Design a collection of strings that allows duplicates and supports insert, remove and a random pick in average constant time, where each stored occurrence is equally likely to be returned. It tests hash map and array layout, index bookkeeping on removal, and how string keys change the cost analysis.

    Software Engineering FundamentalsTechnical Screen
  • LinkedInHardSoftware Engineer
    Reduce Stale Listings in a Job Marketplace

    Design an auditable staleness-detection and remediation engine for a global job marketplace that aggregates heterogeneous signals, enforces graduated interventions, and supports low-latency employer appeals.

    System DesignTechnical ScreenDistributed SystemsEvent-Driven ArchitectureAudit Logging