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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.
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Showing 271–300 of 427 results
- OptiverMediumSoftware EngineerFastest 500-Unit Stretch on a Conveyor Belt From Tick Logs
Given how many units of material a conveyor belt moves during each fixed-length tick, find the maximum average speed over any continuous time stretch covering exactly 500 units, where the stretch may start or end mid-tick.
Coding & AlgorithmsOnline Assessmentsliding-windowtwo-pointersinterpolation - OptiverMediumSoftware EngineerFastest Rolling One-Kilometer Average Speed from 5-Second Distance Samples
Given the meters a runner covers in each 5-second interval, find the fastest average speed over a rolling one-kilometer stretch, defined as the shortest run of intervals ending at each point that covers at least 1000 meters. It tests sliding-window reasoning over large arrays and precise window definitions.
Coding & AlgorithmsOnline Assessment - OptiverHardData ScientistFind missing numbers in sequences
This problem tests pattern recognition and algorithm design for identifying missing terms in a sequence that may follow arithmetic, geometric, polynomial, or linear recurrence rules.
Coding & AlgorithmsOnline AssessmentAlgorithmsPattern RecognitionNumerical Analysis - OptiverMediumSoftware EngineerIdentify OS component causing process starvation
This question evaluates understanding of process scheduling, kernel-level resource allocation, and starvation-related concurrency issues within the operating systems domain.
Coding & AlgorithmsOnline Assessment - OptiverHardSoftware EngineerImplement a Multicore Overheat Prevention Controller
Simulate a multicore thermal controller with delayed workload changes, shared passive cooling, vibration-sensitive active cooling, shutdown and restart thresholds, and transition-only tick output.
Coding & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerImplement price-based order matcher
This question evaluates competency in data structures and algorithmic design for price-based order matching systems, including priority-based matching, efficient order book maintenance, and deterministic tie-breaking requirements.
Coding & AlgorithmsOnline Assessment - OptiverMediumData ScientistMatch alphanumeric patterns in a stream
This question evaluates skills in exact and approximate alphanumeric string matching, streaming pattern lookup, noise-tolerant comparison, and performance-oriented data structures and encodings.
Coding & AlgorithmsOnline Assessment - OptiverMediumData ScientistMinimize moves to transform floor layouts
This question evaluates algorithm design and combinatorial optimization skills, focusing on reasoning about minimal moves, greedy heuristics, and proving optimality within the Coding & Algorithms domain for data-science technical roles.
Coding & AlgorithmsOnline Assessment - OptiverMediumQuantitative TraderOptimize switching puzzle solution
This question evaluates the ability to model a Lights Out-style grid puzzle as a linear system over GF(2), linear algebra skills (Gaussian elimination and null-space reasoning), and combinatorial optimization for minimizing toggle moves.
Coding & AlgorithmsOnline Assessment - OptiverMediumQuantitative TraderSolve a Skyscraper puzzle efficiently
This question evaluates understanding of constraint satisfaction and combinatorial search, testing competency in modeling Latin-square domains with visibility constraints, pruning and uniqueness verification, and algorithmic complexity analysis.
Coding & AlgorithmsOnline Assessment - OptiverMediumSoftware EngineerValidate a Binary Tree Built from Directed Edges
This question evaluates understanding of tree and graph fundamentals including parent-child constraints, duplicate-edge detection, cycle detection, node-degree limits, and in-order traversal semantics.
Coding & AlgorithmsOnline Assessment - OtherMediumSoftware EngineerCompute total after discounting most expensive item
This question evaluates array manipulation and numeric computation skills—specifically identifying the maximum element, applying a percentage discount, and correctly handling fractional results and flooring—within the Coding & Algorithms domain.
Coding & AlgorithmsOnline Assessment - OtherEasySoftware EngineerCount Failing, Passing and Distinction Scores from Percentage Thresholds
Given an array of student exam scores as percentages, count how many students failed with under 50, passed with 50 to 80 inclusive, or passed with distinction above 80, and return the three counts in order. It tests careful handling of inclusive and exclusive boundaries and empty input.
Coding & AlgorithmsOnline Assessment - OtherMediumSoftware EngineerCount Grid Paths Without Three Consecutive Moves
Count monotone grid paths that use exact numbers of right and up moves without ever taking three identical moves in a row. Address empty and one-direction paths, return an exact count, and explain how the limits affect time and space costs.
Coding & AlgorithmsOnline Assessment - OtherEasySoftware EngineerFewest Days to Read a Book When Chapters Cannot Be Split Across Days
Given the reading time available on each day and the time each chapter of a book takes, find the fewest days needed to read every chapter in order when a chapter can never be split across days, or report that the book cannot be finished. It tests simulation with per-day capacity, ordering constraints, and impossible cases.
Coding & AlgorithmsOnline Assessment - OtherEasySoftware EngineerLowest Common Ancestor in an Explicit Binary Tree
Find the lowest common ancestor in a binary tree using explicit child arrays, including identical targets, ancestor targets, and deep trees.
Coding & AlgorithmsOnline Assessment - OtherMediumSoftware EngineerReturn the k-th row of Pascal-like triangle
This question evaluates combinatorics, array manipulation, and space-efficient algorithm design by requiring computation of a specific row of Pascal’s triangle without constructing the full triangle.
Coding & AlgorithmsOnline Assessment - OtherEasySoftware EngineerTrack Workers, Sessions, Promotions, and Bonus Pay
Implement worker sessions, current metadata, promotions, ordered filtering, and time-clipped compensation with historical rates and non-stacking double-pay intervals.
Coding & AlgorithmsOnline Assessment - OtherEasySoftware EngineerValidate Nested Parentheses, Brackets, and Braces
Validate nested parentheses, brackets, and braces with correct handling of empty input, mismatched closing symbols, and unfinished groups.
Coding & AlgorithmsOnline Assessment - OthersEasyData ScientistAnswer ancestor-walk queries on a rooted tree
This question evaluates understanding of tree data structures and ancestor-walk queries, assessing competency in traversing rooted trees, interpreting parent arrays, and designing efficient query-processing methods for large n and q.
Coding & AlgorithmsOnline Assessment - OthersMediumSoftware EngineerAnswer k-step ancestor queries in a rooted tree
This problem tests your ability to optimize ancestor lookups in a tree using the Binary Lifting technique to achieve logarithmic query time.
Coding & AlgorithmsOnline AssessmentTreesBinary LiftingDynamic Programming - OuraMediumSoftware EngineerImplement Server Number Allocation
This problem tests your ability to manage and reuse resources efficiently using data structures that allow for logarithmic time allocation and deallocation within partitioned namespaces.
Coding & AlgorithmsOnline AssessmentData StructuresHeapHash Map - PalantirMediumSoftware EngineerApply Item Coupons with Exact Per-Item Cent Rounding
Implement a checkout calculation engine that applies item-specific coupons to cart lines using exact banker's rounding (round-half-to-even) per unit and returns the final cart total in integer cents.
Coding & AlgorithmsOnline AssessmentSimulationData StructuresMath - PalantirMediumSoftware EngineerStack Item and Category Coupons with an Eighty-Percent Cap
Implement a cart checkout calculator that stacks item and category discounts multiplicatively, caps savings at 80%, and applies round-half-up once per item.
Coding & AlgorithmsOnline AssessmentImplementationMathSimulation - PerplexityMediumSoftware EngineerImplement time-versioned KV store with restore
This question evaluates a candidate's ability to design and implement a time-versioned key–value store, assessing knowledge of temporal data structures, versioning semantics, time-travel and range queries, deletion semantics, and rollback/restoration.
Coding & AlgorithmsOnline Assessment - PersonaHardSoftware EngineerImplement a Versioned Key-Value File Store
Practice a Persona coding interview problem focused on implement a versioned key-value file store. The prompt emphasizes edge cases, clean implementation, and verifiable test behavior without revealing the solution.
Coding & AlgorithmsOnline Assessment - PikaMediumSoftware EngineerImplement text formatter and sum subarray products
This question evaluates algorithmic problem-solving and implementation skills across string formatting (line breaking and space management) and array-based combinatorial computation (sum of subarray products), emphasizing correctness, edge-case handling, and analysis of time and space complexity.
Coding & AlgorithmsOnline Assessment - PinterestMediumSoftware EngineerCollect Pins from Reachable Boards
Implement a breadth-first graph traversal over a collection of boards to collect unique pins in discovery order, handling cycles, shared children, and invalid references.
Coding & AlgorithmsOnline AssessmentGraphBFSHash Table - PinterestMediumSoftware EngineerFind minimum shuttle transfers
Find minimum shuttle transfers 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 & AlgorithmsOnline Assessment - PinterestMediumSoftware EngineerMark and Compact a Heap-Indexed Subtree
This problem tests array manipulation, heap-based tree traversal, and stable partitioning techniques while requiring memory efficiency without modifying the original input.
Coding & AlgorithmsOnline AssessmentArraysTreesHeap
Optiver
Palantir
Perplexity
Pinterest