Software Engineer Coding & Algorithms Interview Questions
Practice 2,743 real Coding & Algorithms interview questions for Software Engineer roles. From companies including Meta, Amazon, Google, Uber, Microsoft.

"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."
Implement sorting and set intersection with input parsing
Write two functions and explain your approach in under two minutes after coding: (A) Sorting: Implement sort_numbers(nums: List[int]) -> List[int] tha...
Maintain k-th largest in a stream
Design and implement a class KthLargest that, given an integer k and an initial list of integers, supports: ( 1) KthLargest(k, nums): constructor; ( 2...
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...
Remove minimum parentheses to balance string
Given a string s containing lowercase letters and the characters '(' and ')', remove the minimum number of parentheses so that the resulting string is...
Compute minimal flips connecting two islands
Given an n x n binary grid of 0s (water) and 1s (land) containing exactly two disjoint islands (cells with 1 connected 4-directionally), return the mi...
Implement pagination and a time-versioned key-value store
Implement two coding tasks: 1) Transaction pagination: Given an in-memory collection of transaction records with fields (txn_id: string, user_id: stri...
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...
Simulate robot path and detect boundedness
A robot starts at (0, 0) facing north on an infinite 2D plane. It executes a command string s consisting of 'G' (move forward one unit), 'L' (turn lef...
Find longest substring with at most k distinct
Given a string s and an integer k, return the length of the longest contiguous substring that contains at most k distinct characters. Provide an O(n) ...
Design a transactional in-memory key–value store
Implement an in-memory key–value store that supports transactions. The system must process these commands: ( 1) SET key value — assign or overwrite a ...
Compute discounted prices in a queue
Given an integer array prices where prices[i] is the price of the i-th item in a checkout line, apply the following rule: for each i, find the first j...
Check balanced parentheses with multiple bracket types
Given a string containing only parentheses '()', determine whether it is balanced. Follow-up: extend the solution to also support '[]' and '{}' with c...
Design variable-size LRU cache
Implement an in-memory cache with least-recently-used eviction where each entry has a variable size in bytes. The cache exposes set(key, value, size),...
Design a queue and analyze tradeoffs
Design a FIFO queue data structure that supports enqueue, dequeue, peek, and isEmpty. Compare implementations using a singly linked list, a dynamic ar...
Maximize operations by removing target-sum pairs
Given an integer array nums and an integer T, in one operation you may remove two elements whose sum equals T. Return the maximum number of operations...
Determine equality of arbitrarily nested sets
Implement a function that determines whether two arbitrarily nested sets are equal. Sets are unordered and contain no duplicates; elements can be inte...
Implement rotation, LRU cache, streaming median, cycle detection
Complete the following coding tasks. For each, provide code, justify time/space complexity, and describe edge cases: 1) Image rotation: Given an n×n i...
Design circular sliding-window ratio tracker
You are given a circular binary array A of length n (A[i] ∈ {0,1}) and a fixed window size w (1 ≤ w ≤ n). Define r (i) as the fraction of 1s within th...
Compute reachability and minimal-time same-type scheduling
1) Given four integers a, b, c, d (1 <= a, b, c, d <= 1000), you may perform the following operations any number of times and in any order: (a, b) -> ...
Implement a nested key-value store
Design and implement a nested key–value store that supports set(path, value), get(path), and delete(path), where path is dot-delimited (e.g., "a.b.c")...