Data Scientist Coding & Algorithms Interview Questions
Practice 335 real Coding & Algorithms interview questions for Data Scientist roles. From companies including Amazon, Google, Two Sigma, Pinterest, Uber.
"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, Fault-Tolerant Distributed Order System
Scenario Round covering distributed-system design and algorithm implementation. Question Design a highly available, low-latency distributed order-proc...
Optimal Stopping for Die Rolls That Bust on Perfect Squares
You repeatedly roll a fair six-sided die and keep a running cumulative sum $S$ of all the values rolled so far (starting from $S = 0$ before the first...
Two Opaque Boxes: Place or Take for Maximum Expected Payoff
You are playing a one-player game with two opaque boxes, both of which start empty. The game lasts exactly 100 turns, and on every turn you must choos...
Find available reservation time slots
Problem You are building an API to show which time slots are available for booking at a restaurant. You are given: - The restaurant’s opening hours (p...
Stone Pile Doubling Game: Can One Pile Be Emptied?
You are given two piles of stones containing a and b stones respectively (both piles start non-empty). You repeatedly apply the following move: - Let ...
Implement sparse vector dot product and cosine similarity
Sparse Vector Class Implement a SparseVector class for high-dimensional vectors where most entries are zero. Representation Assume each vector has: - ...
Implement DelayQueue with Idempotent Task Execution
Scenario Message broker offers DelayQueue where tasks execute at future timestamps, ensuring idempotency on duplicate IDs. Question Implement a delay ...
Implement LRUCache with O(1) Operations and Thread Safety
Scenario High-traffic API needs constant-time eviction cache. Question Implement an LRUCache supporting get(key) and put(key,val) in O( 1). Describe ...
Develop Auto-Complete System for Dish Suggestions
Scenario Search-as-you-type needs dish suggestions with popularity scores. Question Build an auto-complete system using the given (string, score) tupl...
Decode and Explain Ambiguity in Compression Strings
Scenario Compression library that encodes an array as count-value pairs where value is one digit but count may be many digits. Question Implement deco...
Maximize Non-Overlapping Task Scheduling Efficiency
Scenario Job scheduler on a single machine wants to maximise throughput. Question Given tasks with [start, end) times, return the maximum number of no...
How to Design a Proportional Randomized Sampler?
Scenario Randomized promotion engine must pick an item proportional to its score, but scores have no upper bound. Question Design a sampler pick() tha...
Implement Sampling and Minimize Loss in Numerical Coding
Scenario Numerical coding challenges on sampling and loss minimization. Question a) Implement functions to sample from truncated normal distributions ...
Normalize Columns in Binomial Matrix Efficiently
Scenario Write code that creates a 100×100 matrix of Binomial(1, 0. 5) samples and normalizes each column so it sums to 1. Question Provide an efficie...
Automate Python Virtual Environment Setup on Linux Terminal
Scenario Shell script that automates Python virtual-environment setup on a Linux terminal during a tech interview Question Walk through the script lin...
Solve Python Challenges: Reverse String, Palindrome, Fibonacci, Unique List
Scenario Live coding round – four quick Python exercises Question Implement a function that reverses a string in-place. Write code that returns True i...
Find Maximum Sum of Contiguous Subarray Length k
Scenario Monitoring website traffic and needing the highest traffic within any fixed-length time window. Question Given an array of positive integers ...
Determine Circle Intersection Status for Rendering Order
Scenario Graphics engine must evaluate multiple pairs of circles to decide rendering order based on intersection. Question Given an array where each e...
Determine Most Frequent Product Color in Carts
Scenario Online store wants to know which color of product appears most frequently in customers’ carts. Question Implement a function getMaxColor(colo...
Implement Function to Return First n Prime Numbers
Scenario Quick algorithm screen to gauge Python fluency. Question Implement a Python function that returns the first n prime numbers. Hints An optimiz...