Coding & Algorithms Interview Questions
Practice 3,469 real Coding & Algorithms interview questions for 2026. Covers companies like Meta, Amazon, Google, Uber, and Microsoft. Real questions from actual interviews with detailed solutions — ideal for focused interview preparation. Coding & Algorithms interview questions are the single most common technical gate for software engineering roles and are used to evaluate problem framing, algorithm selection, complexity trade-offs, correctness, edge-case reasoning, and clear communication under time pressure. Expect this category to appear in early technical screens and repeatedly across onsite loops at companies that weight it heavily (notably Meta, Google, and Amazon). Interviews will test arrays and strings, trees and graphs, dynamic programming, hashing and two‑pointer techniques, and the candidate’s ability to test and optimize code in a shared editor. Prepare with timed mock interviews, practice in the same editor you’ll use live, and build a progressive schedule that moves from fundamentals to medium/hard problems; typical candidates invest several weeks to a few months of focused practice depending on seniority and target company.
"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."
Maintain the First Value That Appears Exactly Once
Design a data structure that maintains a stream of integers and returns the first value that appears exactly once. Implement: `python class FirstUniqu...
Implement a Leaky Bucket Rate Limiter
Implement a leaky bucket rate limiter. You are given a class template for a rate limiter that controls whether incoming requests should be accepted or...
Retain Top K Elements
Given a list of integers nums and an integer k, return a new list formed from the original list after removing every element except the k largest elem...
Solve Array, Matrix, and Recommendation Problems
During an onsite coding interview, solve the following independent tasks. Problem 1: In-place unique prefix You are given a nondecreasing integer arra...
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. ...
Find First Local Minimum
Given an integer array nums, find the index of the first local minimum. A local minimum is an element that is smaller than its immediate neighbors: - ...
Compute Exclusive Time from Stack Events
Compute Exclusive Time from Stack Events Given entry and exit events from one thread, compute the total exclusive running time of each function. The i...
Find a String Containing Another
Given a list of strings, determine whether any string in the list contains another string from the same list as a contiguous substring. Return one str...
Find the Highest-Cost Top-Level Job
You are given a local JSON file, jobs.json, containing an array of background job records. Each record has: - id: a unique job identifier - parent_id:...
Find Any Available Meeting Room
You are given multiple meeting rooms. For each room, the existing bookings are represented as a list of non-overlapping time intervals sorted by start...
Search Words in a Character Grid
You are given a 2D grid board of lowercase English letters with m rows and n columns. A word can be constructed from letters of sequentially adjacent ...
Find Longest Activatable Server Streak
This question evaluates array algorithm skills, specifically recognition of sliding-window or two-pointer techniques and reasoning about time and spac...
Find Words in a Character Grid
Implement findWords(board, words) for a word-search game. You are given an m x n grid of lowercase English letters and a list of lowercase dictionary ...
Find the Extra Edge
You are given an undirected graph that started as a tree with n nodes labeled from 1 to n. One additional edge was then added between two different ex...
Implement a Fixed-Capacity Deque
Design and implement a fixed-capacity double-ended queue. The data structure is initialized with an integer capacity k and must support the following ...
Minimize a String Using Allowed Swaps
You are given a string s of lowercase English letters and an array pairs, where each element pairs[i] = [a, b] means you may swap the characters at in...
Assign Ads to Browser Positions
Implement a function that assigns ads to browser positions for a single user. You are given: - positions: a list of browser position identifiers, such...
Solve Four Coding Assessment Tasks
Complete the following four independent coding tasks. 1. Find the day a cumulative visit target is reached You are given an array visits, where visits...
Find Largest Adjacent Sorted Difference
Given an unsorted array of integers nums, compute the largest difference between two consecutive elements after the array is sorted in ascending order...
Find a Bounded Subarray and Largest Square
Implement the following two independent coding tasks. Task A: Longest bounded-range subarray Given an integer array nums and an integer limit, return ...