Coding & Algorithms Interview Questions
Practice 2,960 real Coding & Algorithms interview questions for 2026. Coding & Algorithms interview questions for top tech firms like Meta, Amazon, Google, Uber, and TikTok — real questions from actual interviews with detailed solutions — to power your interview preparation. This collection is sharply focused on algorithmic patterns (arrays, strings, sliding windows, trees/graphs, dynamic programming, greedy, two-pointers, and hashing), clean, review-ready code, and the explanation skills that distinguish hires. In 2026 expect familiar medium-to-hard problems plus newer twists: AI-enabled or multi-file coding rounds at some companies, more emphasis on explainability and edge-case reasoning, and occasional real-world performance constraints (streaming, concurrency, memory limits). Interviewers evaluate problem framing, algorithm choice, complexity trade-offs, test-case thinking, and communication under time pressure. Best prep mixes pattern-based practice, timed mock interviews, code-review style polishing, and rehearsed explanations of complexity and tradeoffs. Focus your last-mile prep on writing correct, readable code quickly and on explaining why your solution is robust and efficient for production scenarios.
"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 In-Memory QPS Counter
Implement an in-memory traffic counter. You need to support two operations for each logical key, such as an endpoint, customer, or service name: - rec...
Solve restaurant path and order event tasks
You are given two independent coding tasks. Task 1: Shortest paths in a restaurant grid Context: A restaurant is represented as a 2D grid. The waiter ...
Compute Score Difference in Reversing Array Game
You are given an array of integers. Repeatedly remove the first element of the current array until it becomes empty. Scoring rules: - If the removed n...
Debug a PyTorch U-Net shape mismatch
You are given a PyTorch implementation of a U-Net-like segmentation model that should follow the original U-Net style with valid convolutions (no padd...
Maximize minimum after K decrements
You are given an integer array A of length N and an integer K. You must perform exactly K operations. In each operation, choose any index i and do A[i...
Implement a Coin-Constrained Jump Strategy
You are implementing an autopilot strategy for a simple side-scrolling jump game. A character moves forward automatically. On each game tick, your str...
Validate BFS order queries on a tree
You are given an undirected tree described by two equal-length arrays u and v (each of length n-1). For every index i, there is an undirected edge bet...
Compute max planes shot and session count
Problem 1: Max planes you can shoot before any lands You are given two equal-length arrays: - altitude[i]: the initial altitude of plane i (positive i...
Build a Searchable Sentence Index
Design and implement an in-memory data structure for a collection of sentences. Each sentence has a unique integer id and a text body. Support the fol...
Solve Four Online Assessment Coding Tasks
Implement solutions for the following four independent coding problems. 1. Validate bracket strings You are given an array of strings. Each string ...
Compute Graph Spread and Portfolio Trades
Answer both implementation tasks. Task 1: Maximum connected-component label difference Implement maximumDifference(int gNodes, List<Integer> gFrom, Li...
Solve four algorithmic problems
Answer the following independent algorithmic questions: 1) Count extendable prefixes for '10' subsequences: Given a binary string s and an integer k, ...
Solve string and hashmap coding tasks
You will solve the following coding tasks (independent of each other). Provide clear input/output behavior and handle edge cases. 1) Longest non-repea...
Implement LRU/LFU cache with custom eviction
You are asked to implement an in-memory key-value cache with a fixed capacity. When the cache is full and a new item must be inserted, an eviction pol...
Find Feature Activation Order
You are building a feature-flag system for a product. There are n features labeled 0 to n - 1. Each dependency pair [a, b] means feature a depends on ...
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...
Can a Car Meet a Truck?
A truck's position on a 2D grid is known at each second. You are given an array positions where positions[i] = [x_i, y_i] is the truck's location at t...
Implement Sorted Search and Array Updates
Implement the following independent array functions. Part 1: Search a sorted array Given a sorted array of integers nums in nondecreasing order and an...
Compute dasher pay with peak-hour query
Problem: Dasher pay calculation + peak-hour earnings You are given historical delivery records for a driver (“dasher”). Each record contains: - start_...
Compute max simultaneous drivers last 24 hours
Given delivery intervals (driverId, startTime, endTime) already recorded, implement maxSimultaneousDriverInPast24Hours() that returns the maximum numb...