Senior+ Coding & Algorithms Interview Questions
Senior+ coding rounds don't just test whether you can solve the problem — they test whether you choose the right approach, reason cleanly about complexity, and handle the follow-up that scales the input or changes a constraint. These coding and algorithms questions were all reported from senior-level interviews, so they sit at the harder end of the difficulty band: graph problems with twists, non-obvious dynamic programming, and optimization questions where the naive solution times out. Drill them to sharpen the judgment senior+ interviewers are really evaluating: picking the right data structure on the first try and explaining the trade-off out loud. Most include a detailed solution that covers the reasoning, not just the code.
"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 Top K Largest Elements
This question evaluates a candidate's skill in algorithmic selection and data-structure usage for extracting top-k elements from large arrays, emphasi...
Find Each Cell's Nearest Source
Given an m x n grid containing 1 for source cells and 0 for regular cells, compute for every cell the shortest 4-directional distance to any source ce...
Implement streaming k-way merge with constraints
Implement a function merge_k(iterators, N) that returns the first N items of the global ascending order from k sorted, potentially unbounded iterators...
Solve substring and top‑K pair problems
This multi-part question evaluates algorithm design and data-structure proficiency across string processing (minimum window substring), pair-selection...
Implement store, evaluator, and parser
This question evaluates implementation skills in data structures and algorithms, covering time-based versioning and TTL in an in-memory key-value stor...
Implement array and tree traversal tasks
This question evaluates algorithmic problem-solving and data-structure competency, specifically array-based optimization for single-trade profit and t...
Parse Requests and Compute Balances
This question evaluates input parsing, state management, data validation, and use of basic data structures to track user accounts, friend relationship...
Implement trie-based autocomplete
This question evaluates understanding and implementation of trie data structures for prefix-based retrieval, testing competencies in string algorithms...
Print a binary tree as aligned text
Implement a function that prints (or returns) an ASCII layout of a binary tree. Requirements: - Each node has a string value (assume it contains no sp...
Explain Shell Script Line-by-Line for Data Science Workflows
Scenario Technical screening for a Principal Data Scientist: reviewing shell script and Python classes Question Explain, line by line, what the provid...
Implement User Sessionization From Event Stream
You are building a backend data-processing component that consumes a stream of newline-delimited JSON events. Each event represents a user sending a m...
Merge two sorted arrays in-place
You are given two integer arrays sorted in non-decreasing order, and two integers m and n: - nums1 has length m + n. The first m elements of nums1 con...
Implement bootstrap mean and variance
This question evaluates a candidate's ability to implement bootstrap resampling and compute statistical estimates for the sampling distribution of the...
Maintain an Out-of-Order Step Progress Tree
Maintain an Out-of-Order Step Progress Tree Each progress event contains: `text timestamp: integer step_id: integer parent_step_id: integer or null ru...
Increment a Digit-Array Integer by One
Increment a Digit-Array Integer by One You are given a non-empty array digits in which each element is a single decimal digit (0-9). The array represe...
Quadtree for 2D Geospatial Points
Quadtree for 2D Geospatial Points Design and implement a point quadtree that stores geographic locations on a 2D plane and supports efficient axis-ali...
Highest Salary Using Java Streams
This question tests a software engineer's practical proficiency with the Java Stream API, specifically the ability to perform aggregate operations on ...
Fix the Broken Search Filter in a Book Catalog API
This question tests a backend engineer's ability to implement correct filtering logic, including case-insensitive substring matching, whitespace trimm...
Shortest Path in a Grid with Blocked Cells
This question tests a candidate's practical grasp of graph traversal algorithms applied to 2D grid problems, specifically BFS for unweighted shortest-...
Maximum Sum Skyline
This question tests algorithmic problem-solving with array optimization under a mountain (single-peak) shape constraint. It evaluates practical applic...