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Software Engineer 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 751–780 of 2629 results
- 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 - DatabricksMediumSoftware EngineerImplement a snapshotable set with iterators
This question evaluates understanding of persistent/versioned data structures, iterator semantics, concurrency control, and complexity-aware design for mutable sets, and is categorized under Coding & Algorithms.
Coding & AlgorithmsOnsite - 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 EngineerImplement lazy array and KV store
This problem tests your ability to implement lazy computation using function composition and design a stateful data structure with metadata tracking.
Coding & AlgorithmsOnsiteFunctional ProgrammingData StructuresAPI Design - DatabricksMediumSoftware EngineerImplement run-length encoding and decoding
This question evaluates proficiency in string manipulation and encoding algorithms, specifically run-length encoding and decoding, along with attention to edge cases such as empty inputs and single-character runs and correct handling of repetition counts.
Coding & AlgorithmsOnsite - DatabricksHardSoftware EngineerImplement streaming RLE and bit-packed codec
This question evaluates understanding of data compression algorithms, bit-level manipulation, two's‑complement integer representation, streaming algorithm design, and encoder/decoder state management for 32-bit signed integers.
Coding & AlgorithmsOnsite - 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 EngineerPartition a Target String by Source Substrings
Determine the minimum number of contiguous substrings from a source string required to reconstruct a target string.
Coding & AlgorithmsOnsitestringsgreedysuffix-automaton - DatabricksMediumSoftware EngineerPath Between Two Preorder-Numbered Nodes of an Implicit Fibonacci Tree
Given the order of a recursively defined Fibonacci tree and two nodes labeled by preorder number, return the path between them without building a tree that can hold trillions of nodes. Tests recursive subtree-size reasoning, implicit tree navigation and 64-bit index arithmetic.
Coding & AlgorithmsOnsite - DatabricksMediumSoftware EngineerReferral Credit Tracker with Indirect Referrals
Build a referral credit tracker with account creation, threshold queries, deterministic ordering, and correct credit propagation through indirect referrals.
Coding & AlgorithmsOnsite - DatabricksMediumSoftware EngineerReport the Winner After Every Move on an n x n Tic-Tac-Toe Board
Process a sequence of alternating tic-tac-toe moves on an n x n board and report, after every move, whether player 1 or player 2 has just completed a full row, column, main diagonal or anti-diagonal. Tests efficient incremental win detection, diagonal indexing and correct handling of draws.
Coding & AlgorithmsOnsite - 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 - DatabricksMediumSoftware EngineerSolve graph path, interval deletion, and robbery
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 graph path, interval deletion, and robbery states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsHR Screen - DatabricksMediumSoftware EngineerTic-Tac-Toe Against a Deterministic Automatic Opponent
Build an automated Tic-Tac-Toe opponent with perfect-play minimax, deterministic move ties, board events, invalid attempts, and terminal-state handling.
Coding & AlgorithmsOnsite - DatabricksMediumSoftware EngineerTic-Tac-Toe with Automatic Turns and Board Snapshots
Implement two-player Tic-Tac-Toe with automatic turn changes, board snapshots, rejected moves, winning lines, and full-board draws.
Coding & AlgorithmsOnsite - 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 - DatadogMediumSoftware EngineerCompute sliding window sums by tag
This question evaluates understanding of sequence processing, sliding-window aggregation, filtering by tag, and efficient state management in tagged time-series or event data, testing algorithmic efficiency and correctness.
Coding & AlgorithmsOnsite - DatadogHardSoftware EngineerImplement Prefix Match Filter
This question evaluates understanding of prefix-based string matching, data structure design (hash-based sets and trie/prefix tree), and algorithmic competencies including efficient in-memory storage and deduplication of matches.
Coding & AlgorithmsOnsite - DatadogMediumSoftware EngineerImplement a Snowflake Query Client
This question evaluates API client design, asynchronous query lifecycle management, result retrieval, robust error handling, and secure credential handling for a cloud data warehouse.
Coding & AlgorithmsOnsite - 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 - DecagonMediumSoftware EngineerEnumerate 4x4 Tic-Tac-Toe Games
This question evaluates understanding of recursion and backtracking, exhaustive game-tree enumeration, and state representation for combinatorial game analysis.
Coding & AlgorithmsOnsite - DecagonMediumSoftware EngineerImplement CSAT tracking and call timing
This problem tests your ability to manage stateful data during event processing and calculate exclusive execution times from a stream of nested function logs.
Coding & AlgorithmsOnsiteStackSimulationData Structures
Databricks
Datadog
Decagon