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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
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- 11
- Topics
- 8
- Languages
Showing 1441–1470 of 3276 results
- J.P. MorganMediumSoftware EngineerCount requests dropped when incoming requests exceed available server threads
Simulate a server that receives thread additions and incoming requests as an integer array, where each request permanently consumes one available thread or is dropped, and return how many requests are dropped. It tests careful single-pass array simulation, event ordering, and awareness of integer overflow.
Coding & AlgorithmsTechnical Screen - J.P. MorganEasySoftware EngineerCount substrings and generate TOC
This question evaluates string processing, pattern recognition, and parsing competencies—covering counting and grouping in binary substrings and structured line parsing and numbering for a table of contents—within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - J.P. MorganMediumSoftware Engineer IIFind 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. MorganMediumSoftware EngineerGroup anagrams and count string in grid
This question evaluates algorithmic problem-solving skills in string processing, hashing/grouping and grid traversal/backtracking, along with the ability to analyze time and space complexity and trade-offs.
Coding & AlgorithmsOnline Assessment - J.P. MorganEasySoftware EngineerGroup 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. MorganMediumData ScientistImplement Integer Square Root
This question evaluates numerical algorithm design and integer arithmetic competence, including robustness for edge cases and overflow handling, and is categorized in the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - J.P. MorganMediumData ScientistImplement KNN from Scratch
This problem tests your ability to implement the K-Nearest Neighbors (KNN) algorithm from scratch, focusing on distance computation, sorting, and majority voting logic.
Coding & AlgorithmsTechnical ScreenKNNSupervised LearningAlgorithms - J.P. MorganMediumSoftware Engineer IIImplement 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. MorganEasySoftware EngineerImplement an O(1) LRU Cache
This problem tests your ability to combine a hash map with a doubly linked list to achieve O(1) time complexity for cache operations.
Coding & AlgorithmsTechnical ScreenData StructuresHash MapLinked List - J.P. MorganMediumSoftware EngineerMerge Overlapping Intervals
This problem tests your ability to manipulate array-based data by identifying and merging intersecting ranges using a greedy sorting strategy.
Coding & AlgorithmsTechnical ScreenArraysSortingGreedy - J.P. MorganMediumSoftware EngineerMinimize Operations to Balance Shipments
This question evaluates algorithmic optimization and array partitioning skills, focusing on modeling minimal integer adjustments to equalize partition sums and demonstrating numerical reasoning under constraints.
Coding & AlgorithmsOnline Assessment - J.P. MorganMediumMachine Learning EngineerReturn Every Index Pair Whose Values Sum to a Target
This problem tests your ability to handle frequency counts and index tracking using hash maps to identify all possible index pairs that sum to a specific target, particularly in the presence of duplicate values.
Coding & AlgorithmsTechnical ScreenHash MapArraysAlgorithms - J.P. MorganMediumSoftware Engineer IIReturn 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 ScientistSolve 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 EngineerSplit Modules Across Three Servers to Maximize the Minimum Deployment Difficulty
Assign modules with given difficulty values to three non-empty servers so that the smallest value of |d1 - d2| + |d2 - d3|, over one module picked from each server, is as large as possible. Tests max-min reasoning over partitions, the role of the middle server, and handling of duplicates and large values.
Coding & AlgorithmsOnline Assessment - J.P. MorganMediumSoftware EngineerTwo 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 StreetMediumMachine Learning EngineerBoard Simulation: Bottom-Insert Pieces with Uniform Row and Column Detection
This question evaluates the ability to simulate a 2-D game board and maintain dynamic state invariants, testing array manipulation, state-tracking, and detection of uniform rows and columns under bottom-insert semantics.
Coding & AlgorithmsTechnical Screen - Jane StreetMediumSoftware EngineerBottom-Insertion Connect Game: Detect the First k-in-a-Row Winner
This question evaluates simulation and algorithmic problem-solving skills, focusing on state maintenance for an unbounded grid, efficient detection of k-in-a-row runs in rows and columns, and handling column-wise shifts that can produce simultaneous winners.
Coding & AlgorithmsTechnical Screen - Jane StreetMediumMachine Learning EngineerCode Editor with Block Shrink and Expand (Code Folding)
This question evaluates a candidate's ability to model and manipulate indentation-based hierarchical structures, maintain nested visibility state for collapsed blocks, and map between original file lines and dynamic display numbering.
Coding & AlgorithmsTechnical Screen - Jane StreetMediumMachine Learning EngineerConnect-N on an Infinite Board with Gravity
This question evaluates implementation skills for efficient algorithms and data structures to manage a sparse, unbounded grid with gravity and to detect N-in-a-row runs both vertically and horizontally.
Coding & AlgorithmsTechnical Screen - Jane StreetHardSoftware EngineerDecode an Encrypted Paragraph Tree
This question evaluates skills in string parsing, tree serialization/deserialization, and bijective substitution cipher handling, assessing competency in parsing nested structures, character mapping, and traversal within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - Jane StreetMediumSoftware EngineerEvaluate Expressions with Strictly Positive Integer Intermediate Results
Evaluate arithmetic expressions with a supplied decomposition helper, rejecting nonpositive or fractional intermediate results and preserving exact integer division.
Coding & AlgorithmsTechnical Screen - Jane StreetMediumFrontend EngineerField Layout: getOffset and insert
This question evaluates a candidate's ability to model and maintain ordered field layouts by computing and updating byte offsets, testing competencies in dynamic sequence data structures, cumulative offset tracking, and efficient update/query operations.
Coding & AlgorithmsTechnical Screen - Jane StreetMediumSoftware EngineerImplement Connect Four with bottom push-up
This question evaluates proficiency in data structures, algorithm design, state management, and API design for game mechanics, focusing on board representation, move operations, win detection, and undo/redo functionality.
Coding & AlgorithmsOnline Assessment - Jane StreetMediumSoftware EngineerImplement a Circular Buffer
Implement a fixed-capacity circular buffer (ring buffer) supporting constant-time FIFO operations using wraparound indexing.
Coding & AlgorithmsTechnical ScreenData StructuresQueueArray - Jane StreetEasyMachine Learning EngineerMarketplace Data Store: Order Matching and End-of-Day Reconciliation
This question evaluates understanding of stateful data structures, deterministic order-matching logic, and time-ordered reconciliation of transaction logs, focusing on correct handling of pricing, tie-breaking, and re-opened inventory.
Coding & AlgorithmsTechnical Screen - Jane StreetMediumQuantitative TraderOptimal 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 EngineerOptimize 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 StreetMediumSoftware EngineerPayout-Split Formula Where Every Step Is a Whole Positive Share
Write a parser and evaluator for arithmetic formulas that describe splitting a prize pool into whole-unit shares, where every intermediate computed amount must be a positive whole number or the entire formula is rejected. Tests recursive-descent parsing combined with evaluation rules where a single bad step invalidates the whole result.
Coding & AlgorithmsTechnical Screenparsingrecursionarithmetic - Jane StreetHardSoftware EngineerReach a Target Using Each Number At Most Once
This question evaluates the ability to construct arithmetic expressions from a multiset of numbers and reason about combinatorial search, operator composition, parenthesization, and exact rational arithmetic under constraints.
Coding & AlgorithmsTechnical Screen
J.P. Morgan
Jane Street