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."
Compute build order from dependencies
Given a set of package build dependencies, output a valid build order so that each package is built only after all of its dependencies. The input is a...
Reverse between equal-value nodes in list
Given the head of a singly linked list and a target value v, locate the first two nodes whose values equal v (call them A and B, with A before B) and ...
Design top-K frequency structure
Design an in-memory data structure that supports: add(x) to observe an item, inc(x) to increment its frequency, dec(x) to decrement (deleting when zer...
Design payment-to-invoice matcher with priorities
Design and implement a payment-to-invoice matcher. Inputs: (a) invoices, a list like ["invoice-id-1, 10000, 2022-01-01", "invoice-id-2, 30000, 2022-01...
Decide transform via one-to-one mapping
You are given two strings s and t of equal length over the lowercase English alphabet. In one step, you may pick any character x and replace all its o...
Compute max profit from single stock trade
Given an array prices where prices[i] is the stock price on day i, compute the maximum profit achievable with at most one transaction (one buy and one...
Solve a Skyscraper puzzle efficiently
Design and implement a solver for the Skyscraper logic puzzle on an $N \times N$ grid, where $3 \le N \le 7$. The board is a grid of building heights....
Detect cycles in lists and graphs
Given a singly linked list, determine whether it contains a cycle. Implement an O( 1)-space algorithm and explain the intuition and correctness. Follo...
Implement binary tree in-order traversal
Given the root of a binary tree, return the in-order ordering of its node values. Implement both a recursive solution and an iterative solution using ...
Compute minimum required meeting rooms
Given a list of meeting time intervals [start, end) for many events, determine the minimum number of rooms required so no meetings overlap in the same...
Implement 2D convolution using NumPy slicing
Implement 2D convolution on a 4×4 input and a 3×3 filter with stride 1 using NumPy. Avoid explicit Python loops by relying on array slicing, broadcast...
Count subarrays equal to target
Given an integer array nums and an integer k, return the number of contiguous subarrays whose sum equals k. Provide an algorithm better than O(n^ 2), ...
Insert and merge an interval
You are given a list of pairwise non-overlapping closed intervals [si, ei] sorted by start time, and a new interval [s, e]. Insert [s, e] into the lis...
Heapify an array into a max-heap
Given the array [6, 15, 2, 4, 3, 8, 19], apply heapify to build a max-heap using the standard in-place bottom-up method with a 0-indexed array represe...
Design a single-machine LRU cache
Design an in-memory LRU cache for a single machine using a hash map and a doubly linked list to support O( 1) get and put. Explain how you handle capa...
Design card deck with shuffle and order
Design a playing-card deck library with two methods: shuffle() to return a uniformly random permutation of a standard 52-card deck, and order() to ret...
Implement bounds, minimum, pathfinding, and moving average
Solve the following data-structures problems: ( 1) Given two sorted integer lists A and B, merge them into a single non-decreasing array. Then, for a ...
Find minimum covering substring
Given two strings s and t, return the shortest contiguous substring of s that contains every character of t with at least the same multiplicities. If ...
Solve library SQL and Python tasks
You are given a library domain. Assume these tables: - books(book_id, author_id, title) - authors(author_id, name) - copies(copy_id, book_id, conditio...
Compute reservation diff for largest member
Given copies(copy_id, reserved_by_member_id) and members(member_id, referred_by_member_id), find the member with the largest member_id. Return a singl...