Software Engineering Fundamentals Interview Questions
Practice 603 real Software Engineering Fundamentals interview questions for 2026. Covers core coding, data structures, complexity analysis, debugging, and implementation best practices — real questions from actual interviews with detailed solutions to support focused interview preparation. This category tests the engineering basics interviewers rely on to predict on-the-job performance: correct and efficient algorithms, clean and maintainable code, complexity trade-offs, edge-case reasoning, and the ability to turn requirements into a working implementation under time pressure. Expect heavy weighting at companies like Amazon, Google, and OpenAI, where fundamentals often gate candidates before system design or product rounds. To prepare, prioritize timed problem practice that enforces clear communication, complexity justification, and test-case coverage; drill common data structures and complexity patterns until they become second nature; and rehearse coding on a whiteboard or shared editor to simulate real loop conditions.

"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."
Evaluate C for-loop execution count
In C, variables m and n are both of type int. Consider the following code: `c int m, n; for (m = 0, n = -1; n = 0; m++, n++) n++; ` In standard C ...
Detect impossible binary search comparison sequence
Consider binary search on a sorted array of numeric keys. The following options list possible sequences of key values that the algorithm might compare...
Trace binary search indices in 18-element array
An ordered list of 18 elements is stored in a one-dimensional array A[1..18] (1-based indexing). You perform standard binary search for the element at...
Explain C++ memory, types, and concurrency fundamentals
Explain C++ memory, types, and concurrency fundamentals Answer the following C++ / systems fundamentals questions: 1) C++ class vs struct - What are t...
Parse nested XML inside CDATA
This question evaluates understanding of XML parsing and CDATA handling, including embedded-XML extraction, encoding and escaping concerns, error hand...
Explain AWS access control and frontend typing
This question evaluates cloud infrastructure and access control (EC2, S3 pre-signed URLs, IAM), frontend React fundamentals (hooks and common pitfalls...
Explain OS details and C++ standard differences
This question evaluates familiarity with development environments and proficiency in C++ language standards, focusing on knowledge of operating system...
Write SQL for top spender and non-spenders
This question evaluates SQL querying skills including aggregation and grouping, date/time windowing for previous-calendar-month calculations, joins an...
Clean up all Docker resources
This question evaluates proficiency in Docker resource management, covering containers, images, and volumes and the ability to perform a complete envi...
Differentiate smart pointers and raw pointers
This question evaluates a candidate's understanding of C++ pointer semantics, ownership models, lifetime management, and memory-safety trade-offs betw...
Solve Exact Probability and Expected-Value Exercises
Solve Exact Probability and Expected-Value Exercises Work through the following short quantitative problems. Give exact simplified fractions when the ...
Debug a Transformer bug in an unfamiliar repo
This question evaluates proficiency in debugging Transformer implementations, encompassing codebase navigation, tensor shape and broadcasting reasonin...
Design a task system with assignments
This question evaluates data modeling, API/interface design, and system-design competencies—focusing on entity relationships (Task versus Assignment),...
Detect memory leaks in C++
Detect memory leaks in C++ C++ Memory Leaks: Detection, Integration, and Prevention You are building or maintaining a C++ service/library and need a p...
Assess Spring IoC, AOP, JDBC, Security
Assess Spring IoC, AOP, JDBC, Security Spring Framework — Multi-part Questions Context: You are building/maintaining a Spring-based service for a take...
Write good tests and define integration tests
Write good tests and define integration tests Test Design: Definitions, Trade-offs, and Best Practices Context You're building a small service for a t...
Build a GPU VM Fleet CLI
This question evaluates competency in designing provider-agnostic tooling for managing GPU virtual machines and fleets, covering API integration, life...
Connect Motion Planning, Stability, and LQR Control
Connect four layers of mobile-robot reasoning: transfer-function stability, A* versus RRT planning, temporal-logic safety and liveness, and LQR feedba...
Write a quarterly SQL report and a bash max-file script
This question evaluates proficiency in SQL conditional aggregation and date-based grouping alongside shell scripting skills for recursive filesystem t...
Explain CSS specificity and selector precedence
This question evaluates a candidate's understanding of CSS specificity and selector precedence, focusing on how the browser prioritizes competing styl...