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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
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- 546
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- 11
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Showing 1381–1410 of 1706 results
- SnowflakeMediumSoftware EngineerSolve Matrix and Array Distance Problems
Implement a multi-source breadth-first search to find the shortest path from every compute node to its nearest data warehouse in a grid with obstacles.
Coding & AlgorithmsTechnical ScreenGraphBFSMatrix - SnowflakeMediumSoftware EngineerSolve build ordering and expression evaluation
This question evaluates competency in graph algorithms (topological ordering and cycle detection) and in parsing/evaluating arithmetic expressions with correct operator precedence, associativity, unary operators, and 64-bit integer semantics.
Coding & AlgorithmsTechnical Screen - SnowflakeHardSoftware EngineerSolve scheduling and tree path problems
This problem tests your ability to optimize path calculations in a tree by combining depth-first traversal with a greedy or dynamic programming approach to select paths that satisfy specific constraints.
Coding & AlgorithmsTechnical ScreenTreesDynamic ProgrammingRecursion - SnowflakeMediumSoftware EngineerSort an RGB Record Collection In Place
This question tests the ability to partition an array into three distinct groups (Red, Green, Blue) in a single pass using constant extra space, which is a classic application of the Dutch National Flag algorithm.
Coding & AlgorithmsTechnical ScreenSortingTwo PointersIn-place - SnowflakeMediumSoftware EngineerStack with Constant-Time Minimum over a Sequence of Operations
Design a stack that supports push, pop, top and reading its current minimum in constant time, then run it over a sequence of operations and return what the reads produce. Tests data structure design, duplicate minimum values and keeping auxiliary state consistent on every pop.
Coding & AlgorithmsTechnical Screen - SnowflakeMediumSoftware EngineerTransform tree using counterpart subtree sums
This question evaluates proficiency with binary tree algorithms and in-place subtree aggregation, emphasizing traversal strategies, shape verification, and handling subtree sums under linear-time and O(h) space constraints.
Coding & AlgorithmsTechnical Screen - SnowflakeMediumSoftware EngineerTransform tree with subtree sum mapping
Transform tree with subtree sum mapping 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 - SnowflakeMediumSoftware EngineerTraverse All Reachable Pages With Parallel BFS
Implement a concurrent breadth-first web crawler that discovers all reachable pages from a start URL. The crawler must fetch pages concurrently while maintaining deterministic level-order output and safely handling cycles and fetch errors.
Coding & AlgorithmsTechnical ScreenBreadth-First SearchConcurrencyGraph - SoFiEasySoftware EngineerCount completed car journeys from sensor logs
This question evaluates stateful event-stream processing and per-entity state management, testing the ability to track and reconcile time-ordered sensor events while handling edge cases like unmatched or spurious events.
Coding & AlgorithmsTechnical Screen - SoFiMediumSoftware EngineerDesign a key-value store with getLast
Design a key-value store with getLast 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 - SoFiEasySoftware EngineerFind Smallest Common Row Value
This question evaluates algorithmic problem-solving skills focused on array processing, intersection across multiple sorted sequences, and time/space complexity analysis.
Coding & AlgorithmsTechnical Screen - SoFiMediumSoftware EngineerFind the second most frequent tag
This question evaluates a candidate's ability to perform frequency analysis and stable tie-breaking on a linear sequence, exercising skills in hashing, counting, and handling edge cases such as equal frequencies.
Coding & AlgorithmsTechnical Screen - SoFiMediumSoftware EngineerFormat words into wrapped/justified lines
This problem tests your ability to implement a greedy word-wrapping algorithm that packs words into lines of a fixed width while managing spacing constraints.
Coding & AlgorithmsTechnical ScreenStringsGreedyArray - SoFiMediumSoftware EngineerImplement a multithreaded task executor with semaphores
This question evaluates understanding of concurrent programming, thread-safety, semaphore-style resource management, exception-safe permit release, and extensible API design, and it falls under the Coding & Algorithms category testing concurrency/multithreading, synchronization primitives, and resource management.
Coding & AlgorithmsTechnical Screen - SoFiEasySoftware EngineerReturn All Nodes Reachable from a Starting Vertex
This problem tests your ability to perform a graph traversal (BFS or DFS) to identify all reachable nodes from a specified starting point in an undirected graph.
Coding & AlgorithmsTechnical ScreenGraphsBFSDFS - SonatusHardSoftware EngineerCompute days until a higher reading
This question evaluates proficiency in array processing and the next-greater-element concept, measuring algorithmic reasoning about sequence traversal, comparisons, and managing time/space trade-offs.
Coding & AlgorithmsTechnical Screen - SpacexMediumSoftware EngineerDynamic Island Counts
Report the exact island count after each land addition by tracking only activated cells and merging distinct neighboring components efficiently.
Coding & AlgorithmsTechnical Screen - SpotifyMediumBackend EngineerLongest Contiguous Stretch of Distinct Characters in a String
A Spotify backend technical-screen coding problem: given a string, find the length of the longest contiguous substring in which no character repeats. It tests careful string scanning, linear-time reasoning, and edge cases such as case sensitivity, ties and empty input.
Coding & AlgorithmsTechnical Screen - SquareHardSoftware EngineerImplement transaction network queries
This question evaluates the ability to model and query dynamic graph connectivity and reachability for pairwise transactions, testing competencies in graph representation, dynamic data structures, and reachability queries within the Coding & Algorithms domain and emphasizing practical application of algorithmic concepts.
Coding & AlgorithmsTechnical Screen - SquareEasySoftware EngineerList the Two-by-Two Blocks Covering Each Black Cell
This problem tests your ability to navigate grid coordinates, implement range boundaries, and perform efficient dictionary-based data collection.
Coding & AlgorithmsTechnical ScreenArraysHash MapsGrid - SquarepointMediumData ScientistCompute drawdown, profit, and coin change
This question evaluates a candidate's ability to compute financial time-series metrics and apply algorithmic techniques such as array processing and optimization/dynamic programming to identify maximum drawdown and its indices.
Coding & AlgorithmsTechnical Screen - SquarepointMediumData ScientistCount Index Triplets With an Even Product Modulo a Given Number
From a Squarepoint technical screen: count the triplets of distinct positions in an integer array whose three values have an even product, and return the count modulo a given number. It tests efficient counting on large inputs, parity with zero and negative values, and remembering to apply the required modulo.
Coding & AlgorithmsTechnical Screen - SquarepointMediumData ScientistCount Ways to Reach Step n With a Given Set of Step Sizes
From a Squarepoint technical screen: count the ordered sequences of moves that climb exactly n stairs when every move uses a step size from a given set. It tests careful counting of ordered choices, targets that cannot be reached, and the interviewer's follow-up about reducing the extra space the solution uses.
Coding & AlgorithmsTechnical Screen - SquarepointMediumData ScientistFewest Increment-All-but-One Moves to Make Array Values Equal
From a Squarepoint technical screen: one move adds 1 to every element of an integer array except one chosen element, and you must find the fewest moves that make all elements equal. It tests reasoning about what each move really changes, along with negative values and answers beyond the 32-bit range.
Coding & AlgorithmsTechnical Screen - SquarepointMediumQuantitative ResearcherFind Values Whose Removal Minimizes Pairing Cost
Determine all unique values from an odd-length array whose removal leaves an even-length array that can be partitioned into pairs with minimum total absolute difference.
Coding & AlgorithmsTechnical Screenarrayssortingprefix-sum - SquarepointMediumRisk Technology Software EngineerFind a Target Sum Using Two Sorted Arrays
Tests two-pointer traversal across two distinct sorted arrays to find a target sum, emphasizing linear time complexity and integer overflow prevention.
Coding & AlgorithmsTechnical Screentwo-pointersarraysbinary-search - SquarepointMediumQuantitative TraderImplement EMA Crossovers and Root Solvers
This problem tests your ability to manipulate time-series data using vectorized operations and implement iterative numerical approximations for square roots.
Coding & AlgorithmsTechnical ScreenPandasTime-SeriesNumerical-Methods - SquarepointMediumData ScientistImplement drawdown, single-trade profit, coin change
This question evaluates a candidate's algorithmic problem-solving skills across array and time-series processing, greedy optimization, and dynamic programming, requiring implementation and complexity analysis of maximum drawdown, single-trade profit, and coin change problems within the Coding & Algorithms domain for a Data Scientist role.
Coding & AlgorithmsTechnical Screen - SquarepointHardData ScientistMaximize profit from one or many stock trades
This question evaluates algorithmic problem-solving skills, particularly efficient array processing and profit-optimization across single-transaction and multiple-transaction variants, along with time and space complexity analysis.
Coding & AlgorithmsTechnical Screen - SquarepointMediumQuantitative ResearcherShortest Subarray with at Least K Distinct Values
Determine the minimum length of a contiguous subarray that contains at least k distinct elements. This problem tests sliding-window techniques, hash map management, and linear-time optimization.
Coding & AlgorithmsTechnical Screensliding-windowhash-tabletwo-pointers
Snowflake
SoFi
Spotify
Square
Squarepoint