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."
Compute effective permissions on DAG and prune tree
This set of problems evaluates proficiency in graph and tree algorithms, specifically transitive state propagation and conflict resolution on a DAG (e...
Minimize run-length encoded length with deletions
This question evaluates proficiency in string manipulation, run-length encoding concepts, and dynamic programming-based optimization under deletion co...
Implement bitmap-based block allocator
The bitmap-based block allocator evaluates understanding of data structures, contiguous allocation algorithms, and low-level state management; it is c...
Format words into wrapped/justified lines
This question evaluates practical programming skills in string processing, greedy packing, and careful handling of spacing and edge cases, and falls u...
Compute total revenue from greedy VM rentals
This question evaluates understanding of greedy allocation strategies and the ability to maintain dynamic summaries (tracking current maximum and smal...
Implement four data-structure/string geometry tasks
This multi-part question evaluates manual big-integer string multiplication, robust parsing and tokenization of complex log formats, computational geo...
Compute minimum servers for cyclic tasks
This question evaluates understanding of interval scheduling, overlap detection, and handling cyclic time via modular arithmetic for tasks that wrap p...
Compute suffix sums over waypoints
Problem You are given a batch of 2D waypoint trajectories. - Input: points with shape [B, N, 2], where points[b][i] = (x, y) is the i-th waypoint for ...
Extend BFS maze solver with keys and arrows
This question evaluates mastery of breadth-first search, state-space modeling for grid-based traversal, and handling augmented states like keys and on...
Solve common string/tree/grid interview tasks
This problem set evaluates practical coding competencies including string parsing and sign handling, positional and frequency-based matching for feedb...
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...
Predict output when iterating ordered keys
This question evaluates understanding of ordered maps, iteration semantics, reverse traversal and accumulation of values in code. It is commonly asked...
Measure 45 minutes with two ropes
This question evaluates logical and analytical reasoning about non-uniform processes, constraint-based problem solving, and temporal estimation skills...
Implement weighted random sampling with preprocessing
This question evaluates algorithm design and probabilistic reasoning for weighted random sampling, including data-structure preprocessing, time-space ...
Calculate charge with a single price override
This question evaluates understanding of interval arithmetic, overlap detection and aggregation for time-based billing, plus careful edge-case handlin...
Min boards to cover roof holes
This question evaluates competency in combinatorial optimization and problem modeling for coverage constraints, testing algorithmic reasoning, complex...
Implement Fibonacci generator, balanced BST, frozenset
This question evaluates proficiency in core data structures and algorithms with a focus on Python-specific features, testing generator semantics (yiel...
Implement a debounce function
This question evaluates a candidate's ability to implement a debounce utility using runtime features such as closures, timers, and function-context pr...
Merge overlapping time intervals
This question evaluates competence in interval and array manipulation, sorting-based algorithm design, overlap detection, and efficient time/space com...
Implement topological sort and tree boundary traversal
You are given two separate coding tasks. Problem A — Order courses with prerequisites You have n courses labeled 0..n-1 and a list of prerequisite pai...