Machine Learning Engineer + Data Scientist + Software Engineer 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 O(1) random-sampling set
Design a data structure that supports insert(x), remove(x), and get_random() that returns a uniformly random element among the present items, all in e...
Find longest unique-character substring
Given a string s, return the length of the longest substring without repeating characters. Explain and implement an O(n) sliding-window solution using...
Solve array modulo and parentheses tasks
Implement two tasks: 1) Count subarrays by modulo remainder - Input: integer array nums (length n), integers K (1 ≤ K ≤ 10^ 4) and R (0 ≤ R < K). - Ou...
Convert BST to sorted doubly list
Convert a binary search tree into a sorted doubly linked list in-place. Reuse the existing tree nodes: the left pointer becomes prev and the right poi...
Compute max profit across dated stock quotes
You are given an unsorted list of price records for multiple stocks, each record as (date, symbol, price). Dates may be repeated across different symb...
Implement file deduplication at scale
Implement a command-line tool to find duplicate files in a directory tree. Use OS/pathlib primitives to recursively enumerate files. Apply prefilters ...
Write SQL to Join Merchants and Triple Restaurant Points
You are given: ( 1) a CSV file merchants.csv with columns: merchant_name, merchant_code, category; ( 2) a database table transactions(user_id INT, mer...
Implement and vectorize NumPy Conv2D
Implement a 2D convolution operation from scratch using NumPy only (no TensorFlow or PyTorch). Assume NCHW input shape (N, C_in, H_in, W_in) and weigh...
Compute islands in a binary grid
You are given an m-by-n grid of characters where '1' represents land and '0' represents water. Count the number of connected land masses (islands) usi...
Write SQL with window functions for analytics
Given a table events(user_id, event_time, event_type, value), write SQL to: a) compute each user's rolling 7-day sum of value by day, b) rank each use...
Implement BST vertical traversal and list conversion
Given the root of a binary search tree (BST): 1) Implement vertical order traversal: assign the root column 0, left child column −1, right child colum...
Implement hostname-restricted web crawler
Implement a single-threaded web crawler that, given a starting URL startUrl and an interface getUrls(url) that returns all hyperlinks on the page at u...
Count user sessions from logs
Given a large log file where each line is "timestamp,user,action", compute the number of sessions per user. Assume a session ends if the gap between c...
Count inversions in an array efficiently
Given the array [5, 7, 9, 2, 3, 12, 8, 4], compute the number of inversion pairs (i, j) where i < j and arr[i] > arr[j]. Describe both a naive O(n^ 2)...
Serialize and deserialize a dictionary trie
Question Design and implement serialization and deserialization for a trie (prefix tree) that stores a large dictionary of lowercase English words. Th...
Compute left and right views once
Given the root of a binary search tree, output two lists: the nodes visible from the left side and the nodes visible from the right side, from top to ...
Detect intersection of two linked lists
Given two singly linked lists that may converge to share a common tail, determine whether they intersect and return the first node at which they join....
Reverse sublist between equal-value nodes
Given the head of a singly linked list and a target value v that appears at least twice, reverse the sublist starting at the first node with value v a...
Optimize ribbon piece length by binary search
Given an array lengths of positive integers and an integer k, you may cut each element into pieces of integer length L > 0. Find the maximum L such th...
Compute min operations to transform integers
Given integers A and B, transform A into B using the minimum number of operations. Allowed operations: ( 1) subtract 1 from the current value; ( 2) mu...