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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 9091–9120 of 9403 results
- WayfairMediumApplied ScientistSet Bids for Search Advertising from Business Value
Design search-ad bidding from expected business value, with budget pacing, delayed conversion feedback, auction assumptions, and incremental-profit evaluation.
ML System DesignTechnical Screen - WayfairMediumApplied ScientistSimulate and Compare Multi-Armed Bandit Strategies
Compare epsilon-greedy, UCB1, and Thompson sampling in a reproducible Bernoulli bandit simulation with reward, pseudo-regret, and repeated-run uncertainty.
Machine LearningOnsite - WayfairEasyData ScientistSolve SQL and Python OA tasks
This question evaluates SQL and pandas data-manipulation skills, including joined aggregations over date windows, handling of missing values with median imputation, and multi-criteria sorting and tie-breaking.
Data Manipulation (SQL/Python)Online Assessment - WaymoMediumSoftware Engineer2D Max Pooling That Also Returns the Coordinates of Each Window Maximum
Implement 2D max pooling with a k-by-k window and a stride, and for each window also return the row and column of its maximum, breaking ties by smallest row then column. Tests window indexing without padding, output sizing, and argmax bookkeeping.
Coding & AlgorithmsOnsite - WaymoMediumData ScientistAnalyze User Ride Activity with SQL
Solve four SQL analytics tasks on ride and user tables: inactive users, monthly rides and ratings, low-frequency users by city, and first-versus-third active-month ratings. The walkthrough emphasizes outer joins, date boundaries, aggregation grain, window functions, and weighted averages.
Data Manipulation (SQL/Python)Online Assessment - WaymoMediumData ScientistAssess Routing Experiment Validity
This question evaluates experimental analysis and statistical hypothesis testing skills, including data preparation and joining, interpretation of p-values, and understanding of causal inference and threats to validity in A/B tests.
Statistics & MathOnline Assessment - WaymoMediumFrontend EngineerBuild a Debounced Autocomplete Search Bar
This problem evaluates your ability to implement a robust, performant search component that handles asynchronous race conditions and user accessibility requirements.
Software Engineering FundamentalsOnsiteJavaScriptFrontendDOM - WaymoMediumFrontend EngineerBuild a React naval board
This question evaluates a candidate's ability to design frontend state and UI logic—specifically React component structure, state management, click-handling semantics, and derived sunk-detection logic for a Battleship-style board.
Software Engineering FundamentalsTechnical Screen - WaymoMediumFrontend EngineerBuild an Autocomplete Search Bar With a Hand-Written Debounce
Build an autocomplete search bar that fetches suggestions as the user types, with a hand-written debounce. Tests timer handling across renders, out-of-order responses and request cancellation, keyboard navigation, accessibility, cleanup and testing with fake timers.
Software Engineering FundamentalsOnsite - WaymoMediumSoftware EngineerBuild an Expression That Reaches a Target
This problem tests your ability to use recursion with backtracking or dynamic programming to partition a sequence of numbers and apply operators to satisfy a target value.
Coding & AlgorithmsTechnical ScreenRecursionBacktrackingMemoization - WaymoMediumSoftware EngineerCan You Reach the Last Index?
This problem tests your ability to determine reachability in a sequence using greedy strategy or dynamic programming to optimize pathfinding.
Coding & AlgorithmsOnsiteArraysGreedyDynamic Programming - WaymoMediumSoftware EngineerCharacter at a Position in a Run-Length Encoded String Without Decoding
Given a run-length encoded string such as B1A2E3C1, return the character at each queried position of the decoded sequence without decoding it. Runs can be very long, so the task tests prefix sums over run lengths and fast lookup per query.
Coding & AlgorithmsOnsite - WaymoMediumData ScientistCompare Two Rare-Event Rates with Different Exposure
Compare sparse event rates across unequal mileage using a two-sample Poisson framework, exact conditional testing, and honest uncertainty.
Statistics & MathTechnical Screen - WaymoMediumSoftware EngineerCompute ETA between two map nodes
This problem tests your ability to implement Dijkstra's algorithm to find the shortest path in a weighted directed graph representing a road network.
Coding & AlgorithmsTechnical ScreenGraphsShortest PathDijkstra - WaymoMediumSoftware EngineerCompute Max Pooling Values and Coordinates
This problem tests your ability to manipulate 2D arrays, manage sliding window bounds, and track metadata (indices) efficiently during a data transformation task.
Coding & AlgorithmsTechnical ScreenArrays2D-GridSliding-Window - WaymoMediumData ScientistCompute Ride Metrics in SQL
This question evaluates SQL data manipulation skills, covering joins between normalized tables, timezone-aware date filtering and calendar-month grouping, aggregation and NULL-aware averages, counting distinct and inactive users, and cohort/retention analysis.
Data Manipulation (SQL/Python)Online Assessment - WaymoEasyData ScientistCompute probability match lasts 5 games
This question evaluates understanding of discrete probability, sequential best-of-n match modeling, Monte Carlo simulation for probability estimation, and interval estimation for proportions.
Statistics & MathTechnical Screen - WaymoMediumData ScientistConservative Wait Estimates Cut Conversion and Pickup Time: Did Efficiency Improve?
A ride service showed riders conservative pickup-time estimates; afterwards conversion fell 5% and actual time to pickup fell 25%. Decide whether fleet efficiency really improved and list alternative explanations, testing selection effects and metric design.
Analytics & ExperimentationOnsite - WaymoMediumSoftware EngineerCount Squares Formed by Intersections of Vertical and Horizontal Segments
Given vertical and horizontal line segments defined by start and end points, count the axis-aligned squares whose four corners are all segment intersection points. Tests intersection detection, square enumeration, and faster ways to find which segments cross each other.
Coding & AlgorithmsOnsite - WaymoHardSoftware EngineerCount Squares Formed by Segments
Count distinct axis-aligned squares whose full sides are covered by horizontal and vertical integer-coordinate segments. Normalize and merge collinear coverage, avoid duplicate geometric squares, support overlapping segments and negative coordinates, and index interval coverage efficiently.
Coding & AlgorithmsTechnical Screen - WaymoMediumMachine Learning EngineerDebug Tensor Conversion Bugs
This question evaluates debugging and implementation-level skills in tensor and array manipulation, focusing on aliasing behavior, conversion between column lists and ndarrays, correct handling of non-divisible chunking, and writing tests for these issues.
Coding & AlgorithmsTechnical Screen - WaymoMediumFrontend EngineerDebug an Angular UI from User Reports
This problem tests your ability to debug an Angular component, specifically focusing on Change Detection strategies, memory leaks in RxJS subscriptions, and asynchronous state management.
Software Engineering FundamentalsOnsiteAngularRxJSMemory Management - WaymoMediumSoftware EngineerDecide If a Vehicle Is Ready to Go from Open/End Maintenance Events
Given a vehicle maintenance log of open and end events with timestamps and maintenance types such as oil or brake, decide whether the vehicle is ready to go. The problem tests chronological event processing with a stable tie rule, per-type state tracking, and detecting unmatched ends, overlapping opens, and tasks left open.
Coding & AlgorithmsTechnical Screen - WaymoMediumSoftware EngineerDeduplicate a 256 GB File on a Machine With 128 MB of Memory
Remove duplicate records from a single 256 GB file on a machine with only 128 MB of memory. Tests external-memory techniques such as hash partitioning and external merge sort, skew handling, I/O cost, open-file limits, and preserving the original order.
Software Engineering FundamentalsOnsite - WaymoMediumSoftware EngineerDescribe a Complex Project You Worked On and Why It Was Challenging
Behavioral hiring-manager question: describe a complex project you worked on and explain why it was challenging, often after a resume walk-through. Tests choosing a project that fits the level, naming the real difficulty, personal ownership and outcomes.
Behavioral & LeadershipOnsite - WaymoMediumSoftware EngineerDescribe a Project You Are Proud Of
This question tests your ability to articulate a technical contribution, demonstrate engineering judgment, and communicate impact within a high-stakes team environment.
Behavioral & LeadershipOnsiteBehavioralCommunicationOwnership - WaymoMediumMachine Learning EngineerDesign Large-Scale Inference Serving
This question evaluates understanding of large-scale ML inference systems, assessing competencies in capacity planning, latency and tail-latency engineering, memory and bandwidth estimation, hardware selection (CPUs/GPUs/specialized accelerators), batching and caching trade-offs, and reliability concerns such as out-of-memory prevention and recovery. It is commonly asked to test practical system-design skills for production deployment by requiring back-of-the-envelope QPS and resource estimates and reasoning about operational trade-offs; this belongs to the ML system design category and emphasizes practical application over purely conceptual theory.
ML System DesignTechnical Screen - WaymoMediumSoftware EngineerDesign Reliable Command Delivery Between Autonomous Vehicles and the Cloud
Design a resilient, secure command dispatch and execution system between a cloud fleet management platform and autonomous vehicles operating over unreliable cellular networks.
System DesignOnsiteDistributed SystemsIoTNetworking - WaymoHardSoftware EngineerDesign a Fleet That Collects Mapping Data
Design fleet mapping-data collection with coverage goals, task assignment, offline buffering, resumable uploads, provenance, quality validation, and re-collection workflows.
System DesignOnsite - WaymoMediumSoftware EngineerDesign a Global Small-Image Caching Service
This problem tests the ability to design a highly available, globally distributed caching layer that handles high-throughput small-image delivery while maintaining data consistency and resilience against origin failures.
System DesignTechnical ScreenCachingDistributed SystemsLatency
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