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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.
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Showing 8731–8760 of 9403 results
- UberMediumSoftware EngineerEncode an N-ary tree as a string and decode it back to the identical tree
Design a string format for rooted N-ary trees and implement serialize and deserialize so the decoded tree has the same values, shape and child order. It tests unambiguous encoding of variable child counts, linear-time parsing, iterative handling of very deep trees, and validation of malformed input.
Software Engineering FundamentalsOnsite - UberMediumData ScientistEvaluate ETA Impact on Conversion
This question evaluates a data scientist's skills in causal inference, experimental design, and marketplace analytics, including understanding of confounding, selection bias, interference, and the distinction between correlation and causation.
Analytics & ExperimentationTechnical Screen - UberMediumData ScientistEvaluate Marketplace Changes
This problem tests your ability to design an A/B test for a two-sided marketplace, focusing on network effects, metric selection, and identifying potential interference between treatment and control groups.
Analytics & ExperimentationOnsiteExperimentationA/B TestingMarketplace - UberMediumData ScientistEvaluate Promotions for Uber Eats Users
This question tests the ability to design an A/B test for promotions in a two-sided marketplace, focusing on identifying interference (network effects) and selecting appropriate metrics to measure causal impact.
Machine LearningTechnical ScreenCausal InferenceA/B TestingMarketplace Dynamics - UberMediumData ScientistEvaluate Rider-Incentive Program Impact with Key Metrics
Uber data scientist analytics prompt on evaluating a rider-incentive program, covering experiment design, rider and driver metrics, matching quality, ROI, marketplace externalities, spillovers, and guardrails.
Analytics & ExperimentationTechnical Screen - UberMediumData ScientistEvaluate UberEATS priority delivery and membership
This question tests the ability to design an experiment for a marketplace feature and evaluate its impact on key business metrics like conversion, frequency, and total contribution margin.
Analytics & ExperimentationTechnical ScreenExperimentationMarketplaceCausal Inference - UberMediumData ScientistEvaluate a cold-start rating launch
This question tests the ability to design an evaluation framework for a new feature in a two-sided marketplace while accounting for spillover effects and metrics that represent different stakeholder interests.
Analytics & ExperimentationTechnical ScreenA/B TestingMarketplace AnalyticsCausal Inference - UberMediumSoftware EngineerEvaluate an Arithmetic Expression
This problem tests your ability to parse and evaluate mathematical expressions involving integers, addition, subtraction, multiplication, division, and parentheses using stacks or recursion.
Coding & AlgorithmsOnsiteStackParsingString Manipulation - UberMediumData ScientistEvaluate business value of lower ETA
This question tests the ability to design an experiment that isolates the causal impact of reduced ETA on user retention and to translate these metrics into business value.
Analytics & ExperimentationTechnical ScreenExperimentationCausal InferenceMarketplace Analytics - UberHardData ScientistEvaluate impact without randomized experiments
This question evaluates a data scientist's competence in causal inference and identification strategies for estimating promotion effects from observational longitudinal data, emphasizing challenges such as staggered rollout, interference (spillovers), seasonality, and uncertainty quantification.
Analytics & ExperimentationTechnical Screen - UberMediumData ScientistEvaluate marketplace interventions
This question tests the ability to design an experimentation framework for a two-sided marketplace, specifically addressing interference between supply and demand and selecting appropriate success metrics.
Analytics & ExperimentationOnsiteExperimentationMarketplaceCausal Inference - UberEasyMachine Learning EngineerExplain and test completion-rate gaps
This question evaluates understanding of causal inference, product-metrics analysis, experimental design, and statistical hypothesis testing (including two-sample t-tests) as applied to operational problems in a marketplace.
Machine LearningTechnical Screen - UberHardData ScientistExplain and validate A/B test assumptions
This question evaluates proficiency in experimental design, causal inference, and statistical diagnostics for A/B testing, covering competencies such as randomization integrity, SUTVA/interference, noncompliance, time-varying effects, metric missingness, sequential testing, and heterogeneous treatment effects.
Analytics & ExperimentationTechnical Screen - UberMediumSoftware EngineerFind Any Available Meeting Room
This question evaluates a candidate's competence in handling interval-based scheduling problems, specifically managing interval data and performing efficient searches within sorted bookings to detect potential overlaps.
Coding & AlgorithmsOnsite - UberEasySoftware EngineerFind Earliest Column With One
This question tests the ability to optimize searches in a sorted binary matrix by minimizing expensive API calls through efficient traversal techniques.
Coding & AlgorithmsTechnical ScreenBinary SearchOptimizationMatrix - UberMediumSoftware EngineerFind Earliest Full Connectivity Timestamp
This question evaluates understanding of graph connectivity and temporal event processing, examining how pairwise interactions over time can merge components into a single connected set.
Coding & AlgorithmsTechnical Screen - UberMediumSoftware EngineerFind Kth Smallest in BST
This question evaluates understanding of binary search tree properties, ordered data retrieval, and algorithmic efficiency in locating the k-th smallest element.
Coding & AlgorithmsTechnical Screen - UberHardMachine Learning EngineerFind Robots by Nearest-Blocker Distances
Implement an algorithm to identify all robots in a grid whose four-directional distances to the nearest obstacle or grid boundary match a target query.
Coding & AlgorithmsTechnical Screenmatrixprefix-sumhash-table - UberMediumMachine Learning EngineerFind a Black-Box Convex Function Minimum
This question evaluates proficiency in zero-order optimization and algorithm design, focusing on reasoning about convexity and unimodality when only function evaluations are available.
Coding & AlgorithmsTechnical Screen - UberMediumSoftware EngineerFind a Bounded Subarray and Largest Square
This question evaluates array manipulation and algorithmic problem-solving skills across two tasks: enforcing bounded value ranges within contiguous subarrays and identifying largest uniform square regions in binary matrices, exercising concepts such as range-tracking, efficient data structures, and dynamic programming.
Coding & AlgorithmsOnsite - UberMediumSoftware EngineerFind a Lexicographically Optimal Robot Path with Charging Cells
Find a path in a grid from start to target that lexicographically minimizes charging stations used, peak battery segment length, total moves, and breaks ties by flattened cell indices.
Coding & AlgorithmsTechnical ScreenGraphBFSShortest Path - UberMediumSoftware EngineerFind all dictionary words in a grid
This problem tests your ability to navigate a 2D grid using backtracking and optimize dictionary lookups using a Trie data structure.
Coding & AlgorithmsTechnical ScreenDFSBacktrackingTrie - UberHardSoftware EngineerFind cheapest flight with at most K stops
This question evaluates graph algorithm proficiency and problem-modeling skills, specifically working with directed weighted graphs to optimize path cost under a constraint on intermediate stops.
Coding & AlgorithmsTechnical Screen - UberMediumSoftware EngineerFind earliest common meeting slot
This problem tests interval management and the ability to find a common free window across multiple disjoint sets of busy times while respecting daily working constraints.
Coding & AlgorithmsOnsiteIntervalsSortingGreedy - UberHardSoftware EngineerFind earliest time all riders become connected
Assesses understanding of graph connectivity, temporal event processing, and dynamic graph data-structures for determining when a set of nodes becomes a single connected component.
Coding & AlgorithmsOnsite - UberMediumSoftware EngineerFind leftmost point of maximum brightness
This question evaluates understanding of interval overlap counting, efficient use of ordered data structures for range events, tie-breaking logic, and robustness to numeric edge cases such as large coordinates and floating-point radii.
Coding & AlgorithmsOnline Assessment - UberMediumSoftware EngineerFind minimum activations to absorb all balls
This question evaluates the ability to model Euclidean-distance relations as a static connectivity graph and reason about the minimum number of activations needed to absorb all nodes, testing computational geometry and graph algorithms competency.
Coding & AlgorithmsOnline Assessment - UberMediumSoftware EngineerFind minimum reversals to orient edges away from root
This question evaluates understanding of directed graphs and rooted trees, the ability to reason about edge orientations and minimal reversals, and competency in traversal techniques and complexity analysis.
Coding & AlgorithmsOnline Assessment - UberMediumSoftware EngineerFind next and closest palindromes
This question evaluates string-based numeric manipulation and palindrome construction, including edge-case handling (all 9s, single-digit inputs, length changes), candidate generation and magnitude comparison of large numbers as strings, and carry propagation for fixed-length decimal palindromes.
Coding & AlgorithmsOnline Assessment - UberMediumMachine Learning EngineerFind robots in a grid whose four-direction distances to blockers match a query
Given a grid of robots, blockers and empty cells plus a query of four distances, return every robot whose distances to the nearest blocker or grid edge going up, down, left and right match the query exactly. Tests precise distance definitions, boundary handling and scaling past a per-robot scan.
Coding & AlgorithmsTechnical Screen
Uber