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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 7981–8010 of 9403 results
- SnowflakeMediumSoftware EngineerSerialize a List of Arbitrary Strings into One String and Back, Then Compare Schemes
A two-part coding question that asks you to pack a list of arbitrary strings, which may contain any character, into a single string and rebuild the identical list from that string alone. It tests unambiguous format design, empty-string edge cases, linear-time parsing and a reasoned comparison of alternative encoding schemes.
Software Engineering FundamentalsOnsite - SnowflakeMediumSoftware EngineerSerialize and deserialize a dictionary trie
Snowflake software-engineer onsite coding question: design a compact, robust wire format to serialize and deserialize a dictionary trie. Covers DFS vs BFS encodings, delimiter vs length-prefix framing and escaping, explicit end-of-word markers, streaming, malformed/partial-input handling, forward/backward compatibility, Unicode, compression, memory limits, and O(N) complexity.
Coding & AlgorithmsOnsite - SnowflakeMediumSoftware EngineerSolve Array Distance and Wiki Navigation
This question evaluates array-processing and graph-algorithm skills, specifically minimum-distance computation between marked elements in a one-dimensional array and shortest-path navigation in a directed link graph, plus edge-case reasoning and test-case design.
Coding & AlgorithmsOnline Assessment - 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 - SnowflakeMediumData ScientistSolve and optimize 3Sum and variants at scale
This question evaluates algorithmic problem-solving skills in array processing, deduplication and combinatorial counting, external-memory and streaming algorithm design, and complexity analysis including integer overflow considerations.
Coding & AlgorithmsOnsite - 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 EngineerTime-Versioned Key-Value Store and Time-Window Event Counter
Build a key-value store that keeps every timestamped value of a key and returns the value in effect at a given time, then a counter that answers how many events occurred in a time window. It tests binary search over histories, window semantics and memory bounds.
Software Engineering FundamentalsTechnical 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 - SoFiMediumData ScientistAlign with PM on ranking goals
This question evaluates stakeholder alignment, risk management, product-ranking trade-offs, regulatory and compliance awareness, metric definition, and communication and negotiation skills relevant to delivering an MVP while planning a future ML iteration.
Behavioral & LeadershipTechnical Screen - SoFiMediumSoftware EngineerAnswer Leadership Scenario Questions
This question assesses a candidate's ability to navigate conflicting priorities, advocate for technical excellence, and handle stakeholder management when product roadmaps shift unexpectedly.
Behavioral & LeadershipTechnical ScreenLeadershipStakeholder ManagementConflict Resolution - 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 EngineerDemonstrate project impact and teach something
This question evaluates a candidate's ability to articulate project impact, demonstrate technical leadership, reason about design trade-offs, present measurable outcomes, and teach a technical concept clearly and contextually.
Behavioral & LeadershipTechnical Screen - SoFiHardSoftware EngineerDesign a Random Number Generation API
Design a Random Number Generation API evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignOnsite - SoFiHardSoftware EngineerDesign a Real-Time Suggestions Service
Design a Real-Time Suggestions Service evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignOnsite - 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 - SoFiMediumSoftware EngineerExplain GC, singleton, and OOP principles
This question evaluates understanding of Java runtime memory management (generational garbage collection, marking, compaction), software design patterns (Singleton), and object-oriented design and SOLID principles, testing competencies in performance reasoning, concurrency and thread-safety considerations, design trade-offs, and maintainability.
Software Engineering FundamentalsTechnical Screen - SoFiMediumSoftware EngineerFind Kth Unique Maximum
This problem tests your ability to efficiently manage deduplication and order-statistics using hash maps or sorting techniques while handling multiple input collections.
Coding & AlgorithmsOnsiteHash MapSortingFrequency Count - 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 - SoFiMediumSoftware EngineerImplement tree ops and LRU cache
This question evaluates proficiency with tree-based mutable data structures and cache design, specifically maintaining aggregated state in a full binary tree after leaf updates and implementing an LRU cache supporting O(1) get/put operations.
Coding & AlgorithmsOnsite - SoFiHardData ScientistPlan and validate ranking experiment
This question evaluates skills in experimental design and analytics, covering offline counterfactual replay, interleaving and A/B testing, sample-size and power computation, sequential testing and alpha spending, guardrail monitoring and ramp policies, proxy metrics and covariate adjustment, heterogeneous treatment effect analysis, and governance concerns such as p-hacking and Simpson’s paradox within the Analytics & Experimentation domain for Data Scientist roles. It is commonly asked to probe proficiency in rigorously validating ranking changes while balancing statistical error, operational risk and bias mitigation, and it emphasizes practical application of applied statistical concepts and experiment governance rather than purely theoretical understanding.
Analytics & ExperimentationTechnical 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 - SoFiHardSoftware EngineerScale a key-value store with consistent hashing
Scale a key-value store with consistent hashing evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignTechnical Screen
Snowflake
SoFi