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Coding & Algorithms 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 481–510 of 1080 results

  • InstacartHardSoftware Engineer
    Implement store, evaluator, and parser

    This problem tests your ability to design a robust in-memory data store with versioning and TTL, implement an expression evaluator for dependencies, and parse a specialized stream of matrix data.

    Coding & AlgorithmsOnsiteData StructuresHashingRecursion
  • InstacartMediumSoftware Engineer
    Parse a password from a matrix

    This question evaluates proficiency in grid traversal, sequence-driven state tracking, string manipulation, and boundary/obstacle validation while requiring time and space complexity reasoning.

    Coding & AlgorithmsOnsite
  • InstacartMediumSoftware Engineer
    Parse password from indexed matrix file

    This question evaluates file parsing, matrix indexing with a specified coordinate origin, handling multiple indexed blocks, and string assembly into an ordered password, testing competencies in file I/O, coordinate transformations, and robust input handling.

    Coding & AlgorithmsOnsite
  • InstacartMediumSoftware Engineer
    Pivot order-status counts

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

    Coding & AlgorithmsOnsite
  • InstacartMediumSoftware Engineer
    Resolve a Variable Through Literal and Reference Assignments

    Resolve a target variable through an acyclic chain of named assignments until reaching an integer literal, independent of definition order.

    Coding & AlgorithmsOnsite
  • InstacartMediumSoftware Engineer
    Solve bank, password, expression algorithm tasks

    This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Solve bank, password, expression algorithm tasks states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Coding & AlgorithmsOnsite
  • InstacartMediumSoftware Engineer
    Solve expression evaluator and string decoder

    This question evaluates a candidate's ability in parsing, expression evaluation, and nested string decoding, including handling malformed input, character encoding nuances, and large-file streaming considerations.

    Coding & AlgorithmsOnsite
  • J.P. MorganMediumSoftware Engineer
    Compute longest palindromic subsequence

    This question evaluates understanding of dynamic programming for strings, specifically longest palindromic subsequence concepts such as memoization, bottom-up DP, space optimization and subsequence reconstruction.

    Coding & AlgorithmsOnsite
  • J.P. MorganMediumSoftware Engineer II
    Find the Maximum-Sum Contiguous Subarray

    Implement Kadane's algorithm to find the maximum sum of a non-empty contiguous subarray in linear time and constant auxiliary space, with proper handling for all-negative inputs and potential 64-bit integer overflow.

    Coding & AlgorithmsOnsitedynamic-programmingarrayskadanes-algorithm
  • J.P. MorganEasySoftware Engineer
    Group strings that are anagrams

    This problem tests your ability to efficiently group strings based on their character counts and your knowledge of hash maps to solve anagram-related categorization problems.

    Coding & AlgorithmsOnsiteHash MapString ManipulationAlgorithms
  • J.P. MorganMediumSoftware Engineer II
    Implement Merge Sort

    This problem tests your ability to implement the Divide and Conquer paradigm, specifically the recursive merge sort algorithm, while maintaining stability and managing auxiliary space.

    Coding & AlgorithmsOnsiteSortingDivide and ConquerRecursion
  • J.P. MorganMediumSoftware Engineer II
    Return the K Largest Integers

    This problem tests the ability to efficiently find the k largest elements in an unsorted array using heap-based data structures to optimize for cases where k is significantly smaller than the input size.

    Coding & AlgorithmsOnsiteHeapSortingAlgorithms
  • J.P. MorganMediumData Scientist
    Solve tiling, probability, and nested-radical puzzles

    This problem tests your ability to derive recurrence relations for combinatorial tiling, solve infinite series limits, and calculate exact probabilities using combinations.

    Coding & AlgorithmsOnsiteCombinatoricsDynamic ProgrammingProbability
  • J.P. MorganMediumSoftware Engineer
    Two Sum — Indices Summing to a Target

    This question tests the ability to trade space for time by using a hash map to achieve linear time complexity when finding a pair of elements that satisfy a target sum.

    Coding & AlgorithmsOnsiteArraysHash MapsAlgorithms
  • Jane StreetMediumQuantitative Trader
    Optimal Stopping for Die Rolls That Bust on Perfect Squares

    This question evaluates probabilistic reasoning and optimal stopping competency, testing understanding of Markov decision processes, expected-value calculations, and risk trade-offs in stochastic processes.

    Coding & AlgorithmsOnsite
  • Jane StreetHardSoftware Engineer
    Optimize trade PnL table updates

    Design an incremental PnL tracking engine that efficiently aggregates realized and unrealized profit-and-loss across overlapping predicate views under high-frequency trade and price tick updates.

    Coding & AlgorithmsOnsiteDesignData StructuresCaching
  • Jane StreetEasySoftware Engineer
    Sort trade executions into a canonical order

    This question evaluates a candidate's ability to enforce deterministic ordering and data normalization of time-series trade execution records, testing competencies in multi-key sorting, tie-breaking logic, and performance with large inputs.

    Coding & AlgorithmsOnsite
  • Jane StreetMediumQuantitative Trader
    Two Opaque Boxes: Place or Take for Maximum Expected Payoff

    This question evaluates probabilistic reasoning, expected-value analysis, and sequential decision-making under uncertainty, testing competency in stochastic modeling, combinatorics, and optimization.

    Coding & AlgorithmsOnsite
  • Jump TradingMediumQuantitative Researcher
    Maintain a Fixed-Window Rolling Mean in Constant Time

    Implement an efficient sliding-window mean calculation over a stream or sequence of signed integers. Tests sliding window mechanics, constant-time updates, handling integer overflow, and edge cases.

    Coding & AlgorithmsOnsiteSliding WindowArraysStreaming
  • Lead BankMediumSoftware Engineer
    Process Calendar Events with Deletion, Pagination, and Overlap Queries

    This problem tests your ability to manage a dynamic set of time-interval events using a data structure that allows for logarithmic insertions, deletions, and efficient range-based queries.

    Coding & AlgorithmsOnsiteData StructuresIntervalsPagination
  • Lead BankMediumSoftware Engineer
    Process a Mutable Stock-Price Log

    Design an in-memory mutable stock price log that supports recording prices, tracking update history, calculating percentage changes across dates, and comparing performance between tickers.

    Coding & AlgorithmsOnsitehash-tabledesigndata-structures
  • Lead BankMediumSoftware Engineer
    Solve friend recommendations and time-versioned maps

    This problem tests your ability to model a time-versioned key-value store and leverage graph adjacency structures to perform multi-hop relationship recommendations.

    Coding & AlgorithmsOnsiteBinary SearchGraphsHash Maps
  • LiftoffMediumSoftware Engineer
    Compute the Eddington number from ride distances

    This question evaluates a candidate's competence in array manipulation, ordering/selection techniques, counting thresholds, and algorithmic complexity analysis required to compute the Eddington number.

    Coding & AlgorithmsOnsite
  • LiftoffMediumSoftware Engineer
    Find degrees of connection in a LinkedIn graph

    This question evaluates understanding of graph traversal, reachability and shortest-path concepts along with the ability to manage performance constraints on large sparse graphs.

    Coding & AlgorithmsOnsite
  • LiftoffMediumSoftware Engineer
    Parse and expand an IPv6 address

    This question evaluates proficiency in IPv6 address parsing, string validation, and canonicalization, testing understanding of hexadecimal hextets and the zero-compression (::) rule within the Coding & Algorithms domain.

    Coding & AlgorithmsOnsite
  • LinkedInMediumSoftware Engineer
    Compute graph distance and impacted services

    This problem tests your ability to model a directed dependency graph and perform reachability analysis to identify all downstream services affected by a change in a root service.

    Coding & AlgorithmsOnsiteGraphsBFSDFS
  • LinkedInMediumSoftware Engineer
    Count Distinct Values in a Huge Sorted Array

    This problem tests your ability to optimize search operations in a sorted array by using binary search to skip redundant elements, achieving sub-linear time complexity relative to the total array size.

    Coding & AlgorithmsOnsiteBinary SearchArraysOptimization
  • LinkedInMediumSoftware Engineer
    Count connected land components in a grid

    This question evaluates understanding of grid traversal and graph connectivity concepts, focusing on modeling a 2D matrix as adjacency relationships within the coding and algorithms domain.

    Coding & AlgorithmsOnsite
  • LinkedInMediumSoftware Engineer
    Count islands and distinct shapes

    This question evaluates a candidate's understanding of grid-based graph traversal and connected-component detection, along with the ability to recognize and canonicalize distinct island shapes.

    Coding & AlgorithmsOnsite
  • LinkedInEasySoftware Engineer
    Debug Queues and Solve Arrays

    Tests array traversal, sliding window techniques, and handling wrap-around logic in circular data structures with edge cases.

    Coding & AlgorithmsOnsiteArraySliding WindowTwo Pointers