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."
Solve remembered OA coding tasks
The online assessment reportedly had five coding questions, but only the following three were described clearly enough to reconstruct: 1. Find the top...
Count ordered fragment pairs forming a password
You are given: - A target string password. - A list of N string fragments fragments[0..N-1] (fragments may repeat). Count the number of ordered pairs ...
Resolve Simpson’s paradox in A/B email test
A marketing team tests a new email campaign. They run an experiment for two weeks in two cities (SF and NY) comparing Email A vs Email B. They observe...
Implement TTL Cache and Tree Balance Reporting
Complete both coding tasks. Task A: Time-limited cache Design and implement an in-memory cache where every key expires after a time-to-live duration. ...
Determine Whether Queries Can Zero Array
You are given an integer array nums of length n and a list of range operations queries, where each query is of the form [l, r, val]. Process the queri...
Design query pagination for large datasets
Scenario You are building an API that returns a paginated list of records from a very large dataset (millions+ rows). Clients can specify: - Filters (...
Design a search-to-ads ranking pipeline
Prompt Design a high-level search + ads ranking system for an app where a user issues a query and the product shows a mix of organic search results an...
Decide Which Show to Renew
You are a data scientist at a streaming company deciding whether to renew or cancel content over a 2-year planning horizon. Assume the following: - Ea...
Explain bias-variance, calibration, and model drift
You are interviewing for an applied ML role. Answer the following ML fundamentals questions in a business-facing way (i.e., start from a customer/busi...
Design a job scheduler ETL pipeline system
System Design Prompt Design a Job Scheduler + ETL pipeline system. The system should allow users (or internal services) to: - Define ETL jobs (extract...
Compute streaming sliding-window minimums
Problem You are given an integer array nums of length n and an integer window size k. You scan nums from left to right (streaming). At each index i, y...
How to find the cheapest flight within K stops
Cheapest Flights Within K Stops There are n cities (numbered 0..n-1) and a list of flights: - flights[i] = [u, v, price] means there is a flight from ...
Explain an End-to-End ML Project
In a first-round interview for a lead machine learning role, walk through your background and one machine learning project you led in detail. Your ans...
Optimize Model Serving Under 200ms
A data science team gives you a trained model and asks you to deploy it as an online inference service. The requirement is that a single prediction mu...
Implement vectorized NumPy ops and explain broadcasting
Implement vectorized NumPy code for: (a) computing pairwise cosine similarity between two real-valued matrices X (shape n×d) and Y (shape m×d) without...
Explain JS event loop and related concepts
You are interviewing for a frontend JavaScript position. Answer the following conceptual and practical questions. 1. JavaScript Event Loop, Microtasks...
How to evaluate adding video ads in a game
Case study: Evaluate adding video ads to a mobile game You are the Data Scientist for a free-to-play mobile game. The product team wants to add video ...
Design a Multimodal Training Data Pipeline
Design a backend system for collecting, filtering, and storing training data sent by many clients. Clients upload records that may include large media...
Implement an LRU cache with follow-ups
Coding: Implement an LRU Cache and discuss concurrency Design and implement an in-memory Least Recently Used (LRU) cache data structure. The cache sho...
Explain GRPO-style training for diffusion models
You are given a pretrained image diffusion model that generates images conditioned on text prompts (e.g., a text-to-image model). You now want to fine...