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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
- Companies
- 11
- Topics
- 8
- Languages
Showing 6091–6120 of 9403 results
- OmnissaMediumSoftware EngineerCheck Whether a Singly Linked List Is a Palindrome
Tests the ability to determine if a singly linked list is a palindrome in O(n) time and O(1) auxiliary space using two pointers and in-place list reversal.
Coding & AlgorithmsOnsiteLinked ListTwo PointersIn-Place Reversal - OmnissaMediumSoftware EngineerFind the Celebrity from a Knows Matrix
This problem tests the ability to solve a search problem in O(N) time by utilizing the transitive and exclusionary properties of the 'knows' relationship to eliminate candidates.
Coding & AlgorithmsOnsiteArraysTwo PointersAlgorithms - OmnissaMediumSoftware EngineerFind the Maximum Sum of a Contiguous Subarray
This problem tests the ability to implement Kadane's algorithm to find the maximum sum of a contiguous subarray, specifically focusing on handling negative integers and maintaining optimal time and space complexity.
Coding & AlgorithmsOnsiteArraysDynamic ProgrammingKadane's Algorithm - OmnissaMediumSoftware EngineerPresent a Project Architecture and Your Hardest Technical Decision
This question evaluates your ability to articulate complex system architectures clearly, explain key technical trade-offs, demonstrate personal ownership, and evaluate the long-term impact of architectural decisions.
Behavioral & LeadershipOnsiteSystem ArchitectureTechnical LeadershipTrade-Off Analysis - OmnissaMediumSoftware EngineerPrioritize Two Important Tasks with Competing Deadlines
Assesses how an engineer navigates conflicting priorities, evaluates business versus technical trade-offs, communicates transparently with stakeholders, and executes under tight timelines.
Behavioral & LeadershipOnsiteBehavioralPrioritizationStakeholder Management - OmnissaMediumSoftware EngineerRepeatedly Remove Adjacent Equal Characters
This problem tests your ability to handle recursive reduction patterns in a string using a stack-based approach to achieve linear time complexity.
Coding & AlgorithmsOnsiteStackStringGreedy - OneMain FinancialMediumData ScientistCalculate Break-Even Point and Profit Impact Analysis
This interview question evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer for Calculate Break-Even Point and Profit Impact Analysis states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationTechnical Screen - OneMain FinancialEasyData ScientistCalculate Break-even for New Credit Card Product Launch
This interview question evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer for Calculate Break-even for New Credit Card Product Launch states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationTechnical Screen - OneMain FinancialMediumData ScientistCalculate Profit-Maximizing Price and Validate with Additional Data
Evaluates profit-maximizing pricing from demand curves, marginal revenue, marginal cost, and validation data. Strong answers derive optimal price and quantity, provide examples, and request experiments or elasticity evidence.
Analytics & ExperimentationOnsite - OneMain FinancialMediumData ScientistDetermine Channel Performance with Additional Metrics Needed
This interview question evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer for Determine Channel Performance with Additional Metrics Needed states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationTechnical Screen - OneMain FinancialMediumData ScientistDetermine Optimal Marketing Budget Allocation for Maximum Profit
This interview question evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer for Determine Optimal Marketing Budget Allocation for Maximum Profit states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationOnline Assessment - OneMain FinancialMediumData ScientistDifferentiate and control Type I/II errors
This question evaluates understanding of hypothesis testing fundamentals such as Type I/Type II errors, statistical power and sample size calculation for two-proportion tests, family-wise error rate control (e.g., Bonferroni), and sequential analysis/alpha-spending schemes.
Statistics & MathTechnical Screen - OneMain FinancialEasyData ScientistEvaluate shift from branch to digital channel
This question evaluates a data scientist's ability to analyze channel unit economics, design growth experiments and metrics, and assess operational, fraud, and credit risk implications for shifting acquisition from branch to digital in a credit-card business.
Analytics & ExperimentationTechnical Screen - OneMain FinancialEasyData ScientistExplain decision trees and tree ensembles
This question evaluates understanding of decision trees, splitting criteria for classification versus regression, hyperparameter effects on the bias–variance trade-off, and the mechanics and rationale behind tree-based ensemble methods in the Machine Learning domain.
Machine LearningTechnical Screen - OneMain FinancialMediumData ScientistMaximize Probability of Drawing Two Red Balls
This interview question evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer for Maximize Probability of Drawing Two Red Balls states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Statistics & MathTechnical Screen - OneMain FinancialMediumData ScientistMaximize credit card portfolio profit
This problem tests your ability to model expected profitability by balancing credit risk (probability of default) against revenue generation and defining optimal decision thresholds.
Analytics & ExperimentationTechnical ScreenCredit RiskProfit ModelingDecision Strategy - OneMain FinancialMediumData ScientistOptimize SaaS pricing and profit
This question evaluates pricing optimization, linear demand modeling, capacity-constrained profit maximization, and the impact of subscription churn on lifetime value within an Analytics & Experimentation data-science context.
Analytics & ExperimentationTechnical Screen - OneMain FinancialMediumData ScientistPresent Successful Analytics Project: From Problem to Impact
Evaluates end-to-end analytics project storytelling for an onsite panel presentation. Strong answers cover business context, data, methodology, validation, impact, deployment, stakeholder feedback, and lessons learned.
Behavioral & LeadershipOnsite - OneMain FinancialHardData ScientistPresent a project to non-technical leaders
This question evaluates a data scientist's ability to communicate a modeling project's business framing, metric choices, trade-offs, risk mitigation, and quantified impact while handling cross-functional questions.
Behavioral & LeadershipTechnical Screen - OneMain FinancialHardData ScientistSelect and tune XGBoost hyperparameters
This question evaluates skills in selecting and tuning XGBoost hyperparameters, managing severe class imbalance and sparse one‑hot encodings, handling missing values, and designing compute‑efficient training and grouped cross‑validation to prevent user‑level leakage.
Machine LearningTechnical Screen - OneMain FinancialEasyData ScientistWalk through a DS project end-to-end
This question evaluates end-to-end data science competencies including problem framing, metric design, data sourcing and quality assessment, modeling and evaluation choices, risk identification, impact quantification, and stakeholder communication within the Behavioral & Leadership category for a Data Scientist position.
Behavioral & LeadershipTechnical Screen - OnepayEasySoftware EngineerCount Complete Highway Journeys from Toll Logs
This problem tests string manipulation, hash map usage, and state tracking to identify valid entry-to-exit sequences from an unordered stream of toll logs.
Coding & AlgorithmsTechnical ScreenHash MapsSortingData Streams - OnepayMediumSoftware EngineerDebug and Extend a Device Registry: Status Validation, Active Counts, Bulk Updates
A progressive coding exercise on a device registry: find the bug behind a failing test where a device's status must be allowed for its type, then add validated registration, per-type counts of active devices that omit zeros, and a bulk status update based on maintenance time and failure count. It tests code reading and business logic.
Software Engineering FundamentalsTechnical Screen - OnepayEasySoftware EngineerDesign a Discord-Style Communication Platform
This problem tests your ability to design a scalable real-time messaging architecture, focusing on handling message persistence, state synchronization for offline clients, and channel-based message distribution.
System DesignTechnical ScreenReal-timeScalabilityMessaging - OpenAIMediumSoftware Engineer0-to-1 Ownership, Critical Feedback Both Ways, Defining Success, and Why OpenAI
A software engineer behavioral round covering a 0-to-1 project you built, a time you received negative feedback, how you deliver critical feedback to others, how you define success for a project or product, and why you want to join OpenAI. It tests ownership, self-awareness, communication and motivation.
Behavioral & LeadershipOnsite - OpenAIHardSoftware EngineerA Project You Decided Not to Ship
This question evaluates your product judgment, objective decision-making, and ability to prioritize organizational resources over personal or team output.
Behavioral & LeadershipOnsiteBehavioralLeadershipProduct Judgment - OpenAIMediumSoftware EngineerAI Safety Views and Leadership-Principle Behavioral Questions
A hiring-manager round asks for your view of AI safety and how it would shape your engineering work, followed by standard behavioral questions in the style of Amazon's leadership principles. It tests genuine motivation, judgment when safety and speed conflict, and structured, evidence-based storytelling.
Behavioral & LeadershipOnsite - OpenAIMediumSoftware EngineerAdd Consecutive-Value Bonuses to Grid Paths
Tests dynamic programming on a 2D grid with extended state tracking to incorporate multi-step path history for score bonuses, path counting, and lexicographical path reconstruction.
Coding & AlgorithmsOnsitedynamic-programminggridpathfinding - OpenAIHardSoftware EngineerAggregate Recent Message Events And Active Chats
Design an in-memory aggregation system that tracks rolling window message counts and distinct active entities across chats with bounded memory and O(1) amortized operations.
Coding & AlgorithmsOnsiteSliding WindowData StreamsDesign - OpenAIMediumData ScientistAnalyze A/B Test Results for Subscription Conversion Rates
Evaluates A/B test analysis for a limited-time free trial offer. Strong answers compute paid-conversion lift, account for trial starts and churn, test statistical significance, and make a launch decision using retained paid value, revenue, guardrails, and long-term holdouts.
Analytics & ExperimentationOnline Assessment
OneMain Financial
OpenAI