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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
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- 11
- Topics
- 8
- Languages
Showing 1231–1260 of 1706 results
- RipplingMediumSoftware EngineerCompute median of two sorted arrays
This question evaluates algorithmic problem-solving with sorted arrays, focusing on concepts like binary search, partitioning strategies, complexity analysis, and careful handling of edge cases when computing order statistics.
Coding & AlgorithmsTechnical Screen - RipplingMediumSoftware EngineerCompute peak busy dashers with overlaps
This question evaluates skills in interval-overlap reasoning, sweep-line algorithm design, event creation and deduplication, comparator and tie-breaking subtleties, and asymptotic time/space complexity analysis within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - RipplingMediumSoftware EngineerConvert amounts between multiple currencies
This question evaluates understanding of graph modeling and path-optimization in directed weighted graphs, specifically reasoning about chained conversions and maximizing multiplicative path weights.
Coding & AlgorithmsTechnical Screen - RipplingMediumSoftware EngineerCourier Delivery Cost Tracker
Design a stateful tracker class to record courier delivery intervals and earnings, query running courier payouts, and calculate peak concurrent active deliveries within a specific time window.
Coding & AlgorithmsTechnical ScreenIntervalsLine SweepHash Table - RipplingMediumSoftware EngineerDesign a Driver Payroll System
Design an in-memory driver payroll system that records time-stamped earnings and supports efficient range queries for both individual drivers and company-wide aggregates.
Coding & AlgorithmsTechnical Screenbinary-searchprefix-sumdata-structure-design - RipplingHardSoftware EngineerEvaluate Configurable Rideshare Payout Audit Rules as Data
Implement a generic rule-evaluation engine for a rideshare payout audit tool, where per-fare and per-driver-total rules, each with its own AND-combined conditions, are supplied entirely as data rather than hard-coded branches, using exact integer-cent arithmetic.
Coding & AlgorithmsTechnical Screenrule-enginedesigndata-modeling - RipplingHardSoftware EngineerEvaluate Expense and Trip-Level Rules as Data
Evaluate configurable expense and trip-sum rules using exact cents, reusable typed predicates, strict thresholds, multiple flags, and deterministic result ordering.
Coding & AlgorithmsTechnical Screen - RipplingMediumSoftware EngineerFind median of two sorted arrays
This question evaluates algorithmic problem-solving skills related to sorted arrays and median computation, testing competency in handling numeric order properties and complexity analysis within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - RipplingMediumSoftware EngineerFind the Best and Worst Completion of a Partial Numeric Hand
Find the strongest and weakest five-card completions of a partial numeric hand under custom category and right-to-left tie-break rules while sharing one extensible comparison engine.
Coding & AlgorithmsTechnical Screen - RipplingMediumSoftware EngineerImplement Article Vote Tracking
Design an in-memory article vote tracking system that manages user upvotes/downvotes, detects vote flips to maintain an LRU-style flip history per user, and provides top-k article rankings by net score.
Coding & AlgorithmsTechnical Screenhash-tableheapordered-map - RipplingMediumSoftware EngineerImplement Courier Delivery Cost Tracking
Design an in-memory billing system that tracks courier pay rates over time and calculates prorated delivery costs across half-open time intervals.
Coding & AlgorithmsTechnical ScreenDesignBinary SearchIntervals - RipplingEasySoftware EngineerImplement an article voting tracker
This question evaluates a candidate's ability to design efficient stateful data structures and algorithms for tracking user votes, including correct handling of idempotent repeated votes, vote changes, deduplication, and retrieval of the most recent events.
Coding & AlgorithmsTechnical Screen - RipplingHardSoftware EngineerStudio Session Billing with Rate Schedules and Exact Rounding
Build a command-driven billing ledger where technicians' hourly rates change over time, bookings are deduplicated, and fractional cents are kept exactly until an invoice is printed with a configurable rounding mode. Tests rate lookup by time, idempotency rules, and integer-exact money handling.
Coding & AlgorithmsTechnical Screenhash-mapbinary-searchmoney-arithmetic - RobinhoodHardData EngineerAggregate user logs into 30-minute sessions
This question evaluates data engineering competencies in time-series sessionization, datetime parsing and arithmetic, grouping and aggregation, distinct-count computation, and CSV log processing.
Coding & AlgorithmsTechnical Screen - RobinhoodMediumSoftware EngineerCompute Load Factors in a Service Dependency DAG
Calculate downstream request multipliers for services in a directed acyclic graph (DAG) starting from an entrypoint service, accounting for converging dependency paths and unreachable nodes.
Coding & AlgorithmsTechnical ScreenGraphTopological SortDAG - RobinhoodMediumSoftware EngineerCompute dependency load factors in a DAG
This problem tests your ability to model dependencies in a Directed Acyclic Graph (DAG) and calculate the cumulative 'load' contribution of each node, requiring efficient graph traversal techniques like topological sorting or recursion with memoization.
Coding & AlgorithmsTechnical ScreenGraphDAGRecursion - RobinhoodMediumSoftware EngineerCompute nearest gate distance in grid
This problem tests your ability to perform multi-source Breadth-First Search (BFS) on a grid to find the shortest distance from every cell to the nearest target (gate).
Coding & AlgorithmsTechnical ScreenBFSGraphsGrid - RobinhoodEasySoftware EngineerCompute trigger counts in a DAG
This question evaluates understanding of directed acyclic graphs, graph traversal and accumulation of values across dependency edges, as well as algorithmic efficiency for handling large sparse graphs.
Coding & AlgorithmsTechnical Screen - RobinhoodMediumBackend EngineerCount and Rank Words in a Paragraph
This problem tests string manipulation, hash map usage for frequency counting, and custom sorting logic for deterministic ordering.
Coding & AlgorithmsTechnical ScreenStringsHash MapSorting - RobinhoodEasySoftware EngineerDesign in-memory payment and friendship system
This question evaluates object-oriented design skills, stateful in-memory data structures, request processing, and correctness constraints such as friend relationships, unique request IDs, and atomic balance transfers.
Coding & AlgorithmsTechnical Screen - RobinhoodMediumSoftware EngineerFlatten Fractional-Share Inventory and Record Trade Logs
Process fractional-share buys and sells with exact hundredth units, whole-share market flattening, dollar-order conversion, and ordered inventory-perspective logs.
Coding & AlgorithmsTechnical Screen - RobinhoodMediumData ScientistIdentify Overlapping Sessions and Optimize Coverage
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Identify Overlapping Sessions and Optimize Coverage states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - RobinhoodMediumSoftware EngineerImplement string-based candlestick classifier
This question evaluates string parsing, streaming input processing, numeric validation, and attention to time/space complexity in the Coding & Algorithms category, focusing on efficient single-pass parsing and O(1) extra space constraints.
Coding & AlgorithmsTechnical Screen - RobloxEasyMachine Learning EngineerExtend counter to per-client rate limiting
This question evaluates competency in designing per-client, time-windowed rate limiting using efficient data structures for time-based eviction and counting within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - RobloxMediumSoftware EngineerFind largest digit-sum bucket size
This question evaluates a candidate's competency in combinatorial counting, digit-sum properties, and algorithmic optimization for range queries within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - RobloxEasyData ScientistFind maximum follow depth using recursion
This question evaluates a candidate's competency with recursion, directed graph traversal, cycle detection, and memoization when computing longest-path depths in social-network-style follow graphs.
Coding & AlgorithmsTechnical Screen - RobloxMediumSoftware EngineerFind most frequent call path in logs
This problem tests your ability to parse structured log strings representing nested function calls into a hierarchical tree and identify the most frequently occurring execution path.
Coding & AlgorithmsTechnical ScreenStackHash MapString Manipulation - RobloxEasyMachine Learning EngineerFind the Most Frequent Log Call
This question evaluates a candidate's ability to perform frequency analysis on sequences, demonstrating competency with data structures for counting occurrences and with algorithmic time and space complexity considerations.
Coding & AlgorithmsTechnical Screen - RobloxMediumData ScientistImplement Python Function for Statistical Test P-Values
This question evaluates proficiency in statistical hypothesis testing, p-value interpretation, and implementing distribution-based calculations (Z and Student-t) in code, and it falls under the Coding & Algorithms domain for data scientist roles.
Coding & AlgorithmsTechnical Screen - RobloxMediumSoftware EngineerImplement Sliding-Window Rate Limiter
This problem tests your ability to implement a thread-safe rate limiter using a sliding window algorithm to ensure a user does not exceed a fixed number of requests within a rolling time frame.
Coding & AlgorithmsTechnical ScreenAlgorithmsData StructuresRate Limiting
Rippling
Robinhood
Roblox