Interview Questions
Practice the exact questions companies are asking right now.
"I got asked a hardcore MCM DP question and I saw it on PracHub as well. Solved that question in 5 minutes. Without PracHub I doubt I could solve it in 5 hours. Though somehow didn't get hired, perhaps I guess I solved it too fast? /s"
"Believe me i'm a student here jn US. Recently interviewed for MSFT. They asked me exact question from PracHub. I saw it the night before and ignored it cause why waste time on random sites. I legit wanna go back and redo this whole thing if I had chance. Not saying will work for everyone but there is certainly some merit to that website. And i'm gonna use it in future prep from now on like lc tagged"
"10 years of experience but never worked at a top company. PracHub's senior-level questions helped me break into FAANG at 35. Age is just a number."
"I was skeptical about the 'real questions' claim, so I put it to the test. I searched for the exact question I got grilled on at my last Meta onsite... and it was right there. Word for word."
"Got a Google recruiter call on Monday, interview on Friday. Crammed PracHub for 4 days. Passed every round. This platform is a miracle worker."
"I've used LC, Glassdoor, and random Discords. Nothing comes close to the accuracy here. The questions are actually current — that's what got me. Felt like I had a cheat sheet during the interview."
"The solution quality is insane. It covers approach, edge cases, time complexity, follow-ups. Nothing else comes close."
"Legit the only resource you need. TC went from 180k -> 350k. Just memorize the top 50 for your target company and you're golden."
"PracHub Premium for one month cost me the price of two coffees a week. It landed me a $280K+ starting offer."
"Literally just signed a $600k offer. I only had 2 weeks to prep, so I focused entirely on the company-tagged lists here. If you're targeting L5+, don't overthink it."
"Coaches and bootcamp prep courses cost around $200-300 but PracHub Premium is actually less than a Netflix subscription. And it landed me a $178K offer."
"I honestly don't know how you guys gather so many real interview questions. It's almost scary. I walked into my Amazon loop and recognized 3 out of 4 problems from your database."
"Discovered PracHub 10 days before my interview. By day 5, I stopped being nervous. By interview day, I was actually excited to show what I knew."
"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
"The search is what sold me. I typed in a really niche DP problem I got asked last year and it actually came up, full breakdown and everything. These guys are clearly updating it constantly."
Design a Scalable Calendar Service
Design an online calendar service (think Google Calendar) that supports both individual and shared calendars. Users must be able to create, update, de...
Design alerting for application-to-exchange mappings
Problem: Alerting design for application→exchange mappings You are building a service that receives an ordered stream of mapping events: - register(ap...
Minimum Bills and Coins to Make Change
You are building the change-dispensing logic for a self-checkout cash register. Given a purchase change amount (in dollars, e.g. 6.35), compute the mi...
Debug GPU Resource Allocation
You are given a small codebase for a GPU resource manager. The repository includes a README, logs, and unit tests. Your task is to use the failing tes...
Design camera-footage upload with custody chain
System design prompt You’re building a backend service for uploading recorded body-camera / dashcam footage from client devices (often on unreliable n...
Courier Delivery Cost Tracker
Courier Delivery Cost Tracker You are building the back end for a courier company's dispatch and payouts system. It tracks the deliveries that drivers...
Design Personalized Promotion Recommendations
Design an offline personalized recommendation system for promotional products. The system should periodically generate ranked product or offer recomme...
Multi-Agent Collision Simulator (Unicycle Kinematics)
Multi-Agent Collision Simulator (Unicycle Kinematics) You are given $N$ agents moving in a 2D plane. Each agent is a disk of fixed radius and moves ac...
Implement Connect Four with bottom push-up
Implement a Connect Four variant with bottom push-up. In standard Connect Four a dropped disc falls to the lowest empty cell of a column. In this vari...
Design expense rules engine and return type
Design a Rules Engine for Corporate Card Expenses Context We offer a corporate credit card that employees use for business expenses. Managers set poli...
Minimize Branch Merge Conflicts
You are given several feature branches that must all be merged into the main branch. Each branch contains a sequence of commits, and each commit modif...
How would you evaluate a carousel launch?
You are the data scientist supporting Pinterest's home feed. Product wants to add a horizontally scrollable carousel at the top of the app, similar to...
Design payment fraud detection
Design a machine learning system for fraud detection in an online payment platform. The system should score transactions before or shortly after autho...
Design an A/B test with causal inference
A/B Test Design: Checkout Nudge (Guest-Level Randomization) You own experimentation for an e-commerce checkout flow. You're launching a checkout nudge...
Design Search And Web Crawling Systems
You are asked to design two distinct large-scale systems in a single system-design interview loop: a Facebook-like search product and a distributed we...
Fix the Password Reset Workflow
You are given a small code repository that implements a password reset flow. The repository ships broken: several bugs prevent the application from wo...
Extensible Security-Event Pipeline: Rule Suppression and Plugin-Based Enrichment
You are extending an existing codebase that powers a security-event processing platform. Events flow through a synchronous pipeline: - Collection / In...
Implement and Debug Backprop in NumPy
Two-Layer Neural Network: Backpropagation and Gradient Check (NumPy) You are implementing a fully connected two-layer neural network for multi-class c...
Design a Scalable Likes System
Design a scalable likes service for a large consumer application. Users can like and unlike an item. The system must support these functional requirem...
Build a Reliable Streaming Chat UI
You are building a React-based chat interface where assistant responses stream into the UI token by token in real time (the same UX as a typical LLM c...