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."
Find Shortest Square-Sum Path
This question evaluates algorithmic problem-solving skills with number-theoretic reasoning about perfect squares and the ability to reconstruct a mini...
Implement a Simplified DNS Resolver
This question evaluates understanding of DNS semantics (name normalization, A and CNAME records, alias chains and cycle detection), robust error handl...
Track Island Counts as Land Is Added
Track Island Counts as Land Is Added Problem Implement trackIslandCounts(grid, additions) -> counts. grid is a rectangular array containing 0 for wate...
Compute top-K branches by openings
Compute top-K branches by openings Given a stream of account-opening events (branch_id, user_id, timestamp), design algorithms and data structures to ...
Implement sampling and subarray algorithms
Solve uniform 2D square sampling and longest increasing contiguous subarray. The solution maps Uniform(0,1) to Uniform(-1,1), proves uniformity by ind...
Generate Per-Position Guess Feedback
This question evaluates string-processing skills, array manipulation, and handling of duplicate character counts to produce per-position feedback. It ...
Implement a Composable Event Recommendation Engine
This question evaluates a candidate's skills in software design and implementation for recommendation systems, focusing on modular object-oriented arc...
Solve OA tasks on string, grid path, subarrays
This multi-part question evaluates string manipulation, constrained grid-path optimization with sequential expression evaluation, and counting of pari...
Maximum-Length Unique-Character Subset
This question evaluates a candidate's ability to combine bitmasking with backtracking or subset enumeration to maximize a constraint over combinations...
Word Search in a Letter Grid
This question evaluates a candidate's ability to search for multiple target words within a grid of letters using depth-first traversal and backtrackin...
Path Resolution with Symbolic Links
This question evaluates a candidate's ability to implement filesystem-style path resolution, including handling relative and absolute paths, dot compo...
In-Memory Key-Value Database with Nested Transactions
This question evaluates a candidate's ability to design a data structure that layers transactional state over a committed base, testing skills in nest...
Solve Shortest Paths and Rental Allocation
This question evaluates understanding of shortest-path algorithms and reachability in weighted graphs (including directed vs. undirected handling and ...
Solve Two String Problems
The interview included two coding questions: 1. Exactly one edit apart Given two strings s and t, determine whether they are exactly one edit apart...
Implement obstacle-course run statistics
You are given a TypeScript codebase for tracking race results on an obstacle course. - A Course has a fixed number of obstacles. - A Run stores the ti...
Support Dynamic Range Sums
Implement a data structure over an integer array nums. Part 1: If the array never changes, support sumRange(left, right) that returns the sum of eleme...
Find a valid course order from prerequisites
This question evaluates understanding of graph algorithms, topological ordering, dependency resolution, and cycle detection within the Coding & Algori...
Implement a Merkle-tree repo diff
You are given two snapshots of a source-code repository on disk, each represented by a root directory path. Implement a Merkle tree over the directory...
Solve Two Array Optimization Problems
You are given two coding problems from the same interview round. Problem 1: Split a gold chain fairly An array weights represents the weights of conse...
Count distinct island shapes in a grid
This question evaluates understanding of grid-based connectivity and shape equivalence, exercising skills in graph traversal, spatial normalization, a...