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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 451–480 of 1706 results
- DatabricksMediumSoftware EngineerDesign a rolling event tracker with ranges
This question evaluates understanding of time-series data structures and streaming counters, testing algorithm design, space/time complexity analysis, correctness across edge cases, and handling of large-scale event tracking.
Coding & AlgorithmsTechnical Screen - DatabricksMediumSoftware EngineerDesign an IP filter using CIDR rules
This question evaluates understanding of IP addressing and CIDR notation, bit-level conversion between prefixes and integer ranges, and the design of scalable data structures and algorithms for prefix/range queries, rule priority handling, and rule-set operations (allow/deny semantics).
Coding & AlgorithmsTechnical Screen - DatabricksHardSoftware EngineerDetermine allow/deny for an IP via CIDR rules
This problem tests your ability to efficiently manage and query hierarchical IP address ranges, requiring knowledge of bitwise operations and data structures for range matching.
Coding & AlgorithmsTechnical ScreenBit ManipulationTrieNetworking - DatabricksHardSoftware EngineerEvaluate ACL rules for IP and CIDR
This problem tests your ability to manipulate binary representations of IP addresses and perform efficient prefix matching using CIDR notation, requiring careful bitwise arithmetic and efficient lookup structures.
Coding & AlgorithmsTechnical ScreenBit ManipulationTrieNetworking - DatabricksMediumBackend EngineerFind First Anagram Occurrence
This question evaluates proficiency in string processing, character-frequency analysis, and efficient substring search techniques, measuring competency in algorithmic reasoning and implementation for pattern matching.
Coding & AlgorithmsTechnical Screen - DatabricksHardSoftware EngineerFind Path Between Fibonacci Tree Nodes
This problem tests your ability to map nodes in a recursively defined tree structure without materializing the tree, requiring an understanding of Fibonacci sequences and path-finding algorithms in binary trees.
Coding & AlgorithmsTechnical ScreenTreesRecursionMath - DatabricksMediumSoftware EngineerFind first CIDR block covering IP
This question evaluates a candidate's understanding of IPv4 and CIDR notation, ability to perform prefix-based address containment checks using bitwise reasoning, and competence in parsing and efficient lookup across many ranges.
Coding & AlgorithmsTechnical Screen - DatabricksMediumSoftware EngineerFind k customers with least revenue
This question evaluates a candidate's ability to aggregate per-customer revenue from event streams and perform selection on aggregated totals, testing knowledge of data aggregation, selection algorithms, and efficient use of data structures.
Coding & AlgorithmsTechnical Screen - DatabricksHardSoftware EngineerFind path between nodes in Fibonacci tree
This problem tests your ability to navigate implicit tree structures defined by recurrence relations and your proficiency in pathfinding within large graphs without materializing them.
Coding & AlgorithmsTechnical ScreenTreesRecursionFibonacci - DatabricksHardSoftware EngineerFind shortest path in a Fibonacci-ordered tree
This question evaluates understanding of recursive binary tree structures, preorder indexing, Fibonacci-like size relations, and arithmetic-based navigation for computing paths in an implicitly defined tree.
Coding & AlgorithmsTechnical Screen - DatabricksMediumSoftware EngineerImplement CIDR firewall matcher
This interview question evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer for Implement CIDR firewall matcher states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - DatabricksMediumSoftware EngineerImplement Snapshot Iterator Without Order Guarantees
This question evaluates data-structure design and iterator semantics—specifically snapshot iteration over a mutable, set-like collection without order guarantees—and tests skills in implementing mutation-isolated iteration and analyzing time and space complexity; it belongs to the Coding & Algorithms domain and emphasizes practical implementation.
Coding & AlgorithmsTechnical Screen - DatabricksHardSoftware EngineerImplement a Snapshot Set Iterator
This question evaluates understanding of set data structures, iterator and snapshot semantics, and the ability to reason about time and space complexity when providing stable views over mutable collections.
Coding & AlgorithmsTechnical Screen - DatabricksMediumSoftware EngineerImplement a sliding-window hit counter
This question evaluates understanding of time-based data structures and algorithms for sliding-window counters, including fixed-size array bucketing, handling timestamp collisions within buckets, refactoring for reuse, and time/space complexity analysis.
Coding & AlgorithmsTechnical Screen - DatabricksHardSoftware EngineerImplement an Alternating Tic-Tac-Toe Game
This problem tests your ability to design a robust state machine for a board game, focusing on efficient win-condition checking and clean API design.
Coding & AlgorithmsTechnical ScreenState ManagementArraysGame Theory - DatabricksMediumSoftware EngineerOptimal Commute: Nearest Transit Distance in a City Grid
Tests the ability to solve multi-source shortest path problems on a grid using multi-source Breadth-First Search (BFS). Evaluates graph traversal efficiency, boundary checking, and handling of impassable terrain.
Coding & AlgorithmsTechnical ScreenBreadth-First SearchMatrixGraph - DatabricksHardSoftware EngineerOptimize a SQL query plan tree
This problem tests your ability to manipulate an Abstract Syntax Tree (AST) representing a relational query plan to reduce data processing costs through predicate pushdown and projection pruning.
Coding & AlgorithmsTechnical ScreenTreesRecursionDatabase Internals - DatabricksMediumSoftware EngineerSolve Grid Path and Graph Sampling
This question tests the ability to solve a shortest-path problem with multiple constraints using Dijkstra's algorithm, followed by understanding sampling techniques for connected graph structures.
Coding & AlgorithmsTechnical ScreenDijkstraGraph AlgorithmsDynamic Programming - DatadogMediumSoftware EngineerBuild span trees from unordered trace spans
This problem tests your ability to reconstruct a parent-child hierarchical tree from an unordered collection of trace spans by leveraging parent ID references and sorting mechanisms.
Coding & AlgorithmsTechnical ScreenTreesHash MapsSorting - DatadogEasySoftware EngineerImplement buffered file writer with concurrency support
This question evaluates a candidate's ability to implement buffered I/O and design concurrency-safe APIs, exercising skills in data buffering, performance optimization, and thread-safety.
Coding & AlgorithmsTechnical Screen - DatadogMediumSoftware EngineerImplement log storage and querying
This question evaluates a candidate's skill in designing and analyzing log storage and query systems, covering data layout, indexing strategies, time-range scans with optional filters, and time/space complexity reasoning.
Coding & AlgorithmsTechnical Screen - DatadogMediumSoftware EngineerImplement write with internal buffer
This question evaluates proficiency with buffered I/O, buffer management, memory handling, and performance optimization, including maintaining byte order, handling partial writes, and edge cases across consecutive write/flush/close operations.
Coding & AlgorithmsTechnical Screen - DatadogMediumSoftware EngineerMatch logs to prior queries
This question evaluates understanding of streaming algorithms, string indexing, and set-based matching, focusing on designing efficient online data structures to match stored queries against incoming logs within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - DecagonMediumSoftware EngineerCompute exclusive CPU time from nested logs
This question evaluates the ability to interpret execution logs and compute exclusive CPU time, testing skills in parsing structured logs, reasoning about nested execution intervals, and precise time accounting.
Coding & AlgorithmsTechnical Screen - DecagonHardSoftware EngineerCount Legal Tic-Tac-Toe Games from the Empty Board
Implement an exhaustive search algorithm to count all distinct legal game sequences in 3x3 Tic-Tac-Toe, categorized by outcome.
Coding & AlgorithmsTechnical ScreenBacktrackingDFSGame Theory - DecagonMediumSoftware EngineerDesign a Tic-Tac-Toe Engine
This problem tests your ability to design a state-tracking system for an n x n Tic-Tac-Toe board that allows for constant-time move validation and win detection.
Coding & AlgorithmsTechnical ScreenAlgorithmsData StructuresDesign - DecagonEasySoftware EngineerDesign rolling-window conversation score tracker
Design a rolling-window tracker for streaming conversation scores that supports score updates, rolling average calculation, and maximum score queries.
Coding & AlgorithmsTechnical ScreenSliding WindowDesignQueue - DecagonEasySoftware EngineerImplement a CSAT Sliding Window Tracker
This question evaluates the ability to design and implement efficient data structures and algorithms for a sliding time-window tracker, covering time-based expiration, stateful updates, rolling averages with rounding, and nearest-rank percentile computation.
Coding & AlgorithmsTechnical Screen - DeshawMediumMachine Learning EngineerImplement sqrt and parity-based array rearrangement
In the Coding & Algorithms domain, this prompt evaluates numerical methods and precision handling for implementing a square-root function without library support, together with in-place array manipulation, partitioning and complexity reasoning for parity-based rearrangement, testing competencies in algorithm design, numerical approximation, and space-efficient data transformations. These problems are commonly asked to assess understanding of numerical stability, error bounds and iterative approximation as well as mastery of in-place ordering/partitioning strategies and time/space complexity analysis, requiring both conceptual understanding of mathematical properties and practical implementation ability.
Coding & AlgorithmsTechnical Screen - DeshawMediumSoftware EngineerMaximum L1 Distance Between Equal-Length Subarrays
Tests recognizing that non-negative L1 terms allow reducing subarray search to full diagonal overlaps across two arrays, requiring O(n * m) time and 64-bit integer handling.
Coding & AlgorithmsTechnical Screenarraysmathtwo-pointers
Databricks
Datadog
Decagon