Tech Interview Preparation

In the last 15 years, I have interviewed 800+ Software Engineers across Google, Paytm, Amazon & various startups. Here are the most actionable tips I can give you on how to approach  solving coding problems in Interviews  (My DMs are always flooded with this particular question) 1. Use a Heap for K Elements      - When finding the top K largest or smallest elements, heaps are your best tool.      - They efficiently handle priority-based problems with O(log K) operations.      - Example: Find the 3 largest numbers in an array.   2. Binary Search or Two Pointers for Sorted Inputs      - Sorted arrays often point to Binary Search or Two Pointer techniques.      - These methods drastically reduce time complexity to O(log n) or O(n).      - Example: Find two numbers in a sorted array that add up to a target.   3. Backtracking    - Use Backtracking to explore all combinations or permutations.      - They’re great for generating subsets or solving puzzles.      - Example: Generate all possible subsets of a given set.   4. BFS or DFS for Trees and Graphs      - Trees and graphs are often solved using BFS for shortest paths or DFS for traversals.      - BFS is best for level-order traversal, while DFS is useful for exploring paths.      - Example: Find the shortest path in a graph.   5. Convert Recursion to Iteration with a Stack      - Recursive algorithms can be converted to iterative ones using a stack.      - This approach provides more control over memory and avoids stack overflow.      - Example: Iterative in-order traversal of a binary tree.   6. Optimize Arrays with HashMaps or Sorting      - Replace nested loops with HashMaps for O(n) solutions or sorting for O(n log n).      - HashMaps are perfect for lookups, while sorting simplifies comparisons.      - Example: Find duplicates in an array.   7. Use Dynamic Programming for Optimization Problems      - DP breaks problems into smaller overlapping sub-problems for optimization.      - It's often used for maximization, minimization, or counting paths.      - Example: Solve the 0/1 knapsack problem.   8. HashMap or Trie for Common Substrings      - Use HashMaps or Tries for substring searches and prefix matching.      - They efficiently handle string patterns and reduce redundant checks.      - Example: Find the longest common prefix among multiple strings.   9. Trie for String Search and Manipulation      - Tries store strings in a tree-like structure, enabling fast lookups.      - They’re ideal for autocomplete or spell-check features.      - Example: Implement an autocomplete system.   10. Fast and Slow Pointers for Linked Lists      - Use two pointers moving at different speeds to detect cycles or find midpoints.      - This approach avoids extra memory usage and works in O(n) time.      - Example: Detect if a linked list has a loop.   💡 Save this for your next interview prep!

When I started preparing for tech interviews, I made myself a promise. I won’t spend money on expensive courses. I’ll make it with free resources only. At first, it was tough. Too many topics, too many doubts. But slowly, I found a path that worked for me. And with these resources, I cracked my interviews. Here’s what really helped me: ✅ LeetCode – My go-to for DSA. The questions and patterns made problem-solving clear. ✅ Aditya Verma (YouTube) – He made Dynamic Programming, Recursion, and Stacks feel simple. ✅ Striver’s Graph Series (aka Raj Vikramaditya ) – Graphs were always scary, but his explanations clicked. ✅ freeCodeCamp – Anytime I wanted to explore a dev skill, I trusted them. ✅ C++ Basics – W3Schools.com and GeeksforGeeks helped me build my foundation. ✅ System Design (ByteByteGo) – Opened my eyes to high-level design concepts. ✅ InterviewBit Sheets – Perfect for last-minute revision of OOPS, DBMS, CN, OS. ✅ GateSmashers – Helped me rebuild my CS fundamentals from scratch. This list is not random; it’s my actual journey. I stuck to it, practiced daily, and it worked. If you’re preparing, I hope this gives you some direction. #sde #tech #interview #connections #networking LinkedIn LinkedIn News

When I interviewed candidates for our team at Microsoft, one thing always set the best apart. Specificity. Their answers showed that they did their research. They knew exactly why we were hiring and how their background fit — and they gave specific examples to prove it. This was one of the most consistent things across our best hires, so much so that I actually ended up using it as a screening test. If I could replace Microsoft with a competitor (Google, Amazon, etc.) and their answer still worked, it wasn’t a good answer. The people who gave catch-all answers tended to show that they didn't do much research and the convo progressed. Those interviews were generic and boring. But the people who could tell me exactly what was happening and how they could make an impact? Those conversations were a blast and those candidates stood out. So when you’re preparing for your next interview, use this 3 step process: 1. Research the heck out of the company and hiring team 2. Draft up answers that use specific examples and focus on the company’s needs 3. For each answer, ask yourself, “does this answer make sense if I swap in a competitor?” If it does, you need to be more specific! If it only makes sense with your target company, you’re in great shape to crush this thing.

If you're 54+ and not getting hired, it's not your resume, experience, or skills. It's three assumptions hiring managers make about you. They think you're expensive - assuming you want the same salary from 10 years ago when inflation did the math for them. They think you can't learn new technology - complete nonsense, but it's their bias. They think you won't stick around long enough to justify the hiring investment. How to combat this: - Lead with energy, not just experience - Show curiosity alongside qualifications - Update your LinkedIn photo to something recent - Address salary expectations directly in conversations - Demonstrate tech fluency through examples, not just claims The market desperately needs experienced professionals who can mentor, strategize, and execute without the drama. Don't let their ageism rob you of opportunities you've earned through decades of expertise. Your experience is an asset, not a liability. Position it that way. Sign up to my newsletter for more corporate insights and truths here: https://vist.ly/49jic #ageism #jobsearch #over50jobs #careeradvice #matureworkers #executiverecruiter #eliterecruiter #jobmarket2025 #profoliosai #careerstrategy

When people ask me, “How did you get into Google” ? — they often expect a shortcut or some secret trick. Here’s the truth: there is no shortcut. But there is a strategy. 💪 If you're preparing for big tech interviews (Google, Meta etc.), here’s what I’ve learned first-hand: ✅ 1. Master fundamentals, not just patterns. Instead of memorizing 100+ Leetcode solutions, deeply understand how and why data structures work (e.g., why a trie is used for prefix matching, why dynamic programming optimizes overlapping subproblems). ✅ 2. Solve problems consistently. Quality beats quantity. Solving 2 problems deeply every day > solving 10 problems quickly without understanding. ✅ 3. Think out loud. In interviews, your approach matters more than your final answer. Interviewers want to know how you think, debug, and improve. ✅ 4. Mock interviews are game-changers. Simulate the real interview environment with friends or mentors. You’ll build confidence and identify blind spots. ✅ 5. Embrace feedback and failure. I’ve faced rejections too. Instead of feeling defeated, I treated each one as a free lesson to level up. --- Today, as a Software Engineer at Google, I still use these principles daily — solving real-world problems at scale. ✨ To anyone preparing: You don’t have to be a genius. You just have to keep showing up, learning, and believing in yourself. If you'd like, I can share a detailed roadmap or my personal prep strategy in a future post — just comment “Interested” below! ⬇️ For 1:1 conversations please connect here: https://lnkd.in/ga_5bi57 #Google #SoftwareEngineering #InterviewPreparation #DSA #WomenInTech #CareerAdvice

Stop collecting certificates. Start building projects that actually get interviews. 10 videos. 1.4M views. Everything from SQL to Python to building your actual portfolio website. Alex built these projects specifically for beginners who need portfolio pieces that actually get interviews. 𝐓𝐡𝐞 𝐥𝐢𝐧𝐞𝐮𝐩: • SQL Data Exploration with COVID data (1h 17min) • Tableau dashboard creation from scratch (52min) • Data cleaning in SQL - the skill everyone needs (54min) • Python correlation analysis for real datasets (1h) • Portfolio website setup - completely free (35min) • Amazon web scraping project (47min) • Full Excel project walkthrough (40min) • Power BI guided project (42min) • Crypto API automation (51min) Follow along, build it yourself, customize with your own data. 𝐖𝐡𝐲 𝐭𝐡𝐢𝐬 𝐰𝐨𝐫𝐤𝐬: - Real-world data problems, not toy datasets - Tools that companies actually use - Projects you can explain in interviews - Code you can show on GitHub I've seen hundreds of portfolios. The ones that get callbacks show actual data cleaning, analysis, and visualization skills. Not just certificates. 𝐀𝐥𝐞𝐱 covers SQL → Python → Tableau → Excel → Power BI. That's the exact stack most data analyst roles require. Start with the SQL project. It's the foundation everyone needs. ♻️ Save it for later or share it with someone who might find it helpful! 𝐏.𝐒. I share job search tips and insights on data analytics & data science in my free newsletter. Join 16,000+ readers here → https://lnkd.in/dUfe4Ac6

There are so many people who asked me about my Goldman Sachs internship—how did I apply, what's the procedure… so here’s my journey! 🚀 I secured my internship through Goldman Sachs' Engineering Campus Hiring Program (ECHP), and here’s a breakdown of my experience: 📌 1. Application Process ✅ Applied via the official portal after participating in an off-campus drive. ✅ Prioritize filling out the form accurately before proceeding to the first online aptitude test. 📝 2. Aptitude Round ✅ Conducted on Hackerrank with 7 sections and 70 questions. ✅ Sections: Numerical Computations, Reasoning (Numerical, Abstract, Diagrammatic, Logical), and Comprehension. ✅ Marking: +5 for correct answers, -2 for incorrect ones. ✅ Attempted 50-55 questions correctly—a crucial elimination round. 🎓 3. Coursework ✅ Completed 3 Coursera specialization courses that helped in the upcoming rounds. 💻 4. Technical Test (Coding + MCQ) ✅ Another Hackerrank test, 1-hour time limit. ✅ 11 questions (MCQs + Coding) from Core CS Fundamentals and DSA. ✅ Marking: +5 for correct, -2 for incorrect answers. ✅ Divided into: 🔹 Programming questions 🔹 MCQs (OS, DBMS, OOPs, Networks) 🔹 Personal Introduction Section (2 theoretical questions) ✅ Proctored test with strict plagiarism checks. 🔥 TIP: Solve the easy coding question completely first, and avoid guessing MCQs. 🗣️ 5. Interview Rounds 📍 Round 1 (Technical Interview) ✅ Zoom interview, focused on DSA & basic OS questions. ✅ Solved 3 DSA questions (1 Array, 2 Binary Trees). ✅ Explained time & space complexity for each solution. 📍 Round 2 (Technical Interview) ✅ Covered DSA & DBMS concepts along with SQL questions. ✅ Solved one puzzle question correctly. 📍 Round 3 (Technical Interview) ✅ Started with introduction, then moved to one hard DSA question. ✅ Wrote working, optimized code with proper time & space complexity analysis. ⏳ 6. Post-Interview Experience ✅ Waited for the results, which were communicated via email within 20 days. 🚀 7. Life-Changing Tips ✔️ First two online rounds had major eliminations—prepare well! ✔️ Have faith in your practice and skills—this is key. ✔️ Solve previous Goldman Sachs DSA questions. ✔️ Read interview experiences of others and reach out for help. ✔️ Strong fundamentals in DBMS, OOPs, OS are a must. Hope this helps! Feel free to connect if you have any questions. 🚀 #GoldmanSachs #hiring #HiringProcess #internship #tech

Hard Truth: Data Structures - The Unavoidable Interview Reality Here's a pattern I've noticed recently that every software professional needs to hear: Even if you haven't used a binary tree in years, you WILL face data structure questions in your next interview. Here's why this matters: The Interview Reality Check: 1. FAANG-level companies:    - Will absolutely grill you on data structures    - Expect implementation from scratch    - Want optimal solutions 2. Startups:    - May seem more relaxed    - Still include DS questions in their process    - Use them to evaluate problem-solving 3. Even Frontend Roles:    - React state management? That's a tree    - Event handling? Welcome to queues    - Browser history? That's a stack What I've Observed: - Brilliant developers failing interviews because they're rusty on basics - Senior engineers stumbling on LinkedList questions - Tech leads getting rejected for missing optimal solutions The Smart Approach: 1. Keep a "DS Emergency Kit":    - Arrays & String manipulation    - Hash Tables implementations    - Tree traversals    - Graph basics    - Stack & Queue operations 2. Monthly Refresh Routine:    - Solve one problem per structure    - Review time complexities    - Practice explaining your approach Common Mistakes: - Thinking "I don't use this at work, so I won't study it" - Starting interview prep too late - Focusing only on coding, ignoring theory Quick Tips: 1. LeetCode Medium is your friend 2. Always write clean code in interviews 3. Think aloud during problem-solving 4. Review basic implementations monthly Core Data Structures You MUST Know: 1. Arrays    - What: Continuous memory blocks    - Why: Foundation of most data operations    - Real use: Instagram's photo feed, Spotify's playlist management 2. Linked Lists    - What: Connected nodes with next/prev references    - Why: Dynamic memory allocation    - Real use: Undo/Redo functionality in text editors 3. Hash Tables    - What: Key-value pair storage    - Why: Lightning-fast O(1) lookups    - Real use: Database indexing, caching systems 4. Stacks (LIFO)    - What: Last-In-First-Out structure    - Why: Track execution context    - Real use: Browser history, Function call management 5. Queues (FIFO)    - What: First-In-First-Out structure    - Why: Order preservation    - Real use: Print spoolers, Message queues in distributed systems 6. Trees    - What: Hierarchical data structure    - Why: Organized data relationships    - Real use: File systems, DOM in web browsers 7. Graphs    - What: Nodes connected by edges    - Why: Complex relationship mapping    - Real use: Social networks, Google Maps, Netflix recommendations 1. Practice implementing from scratch 2. Study time complexity for each operation 3. Learn when to use which structure Action Items: 1. Pick one structure weekly 2. Implement it in your preferred language 3. Solve 2-3 related problems 4. Document real-world applications

I’ve bombed so many interviews because I thought memorizing answers would make me sound prepared. Turns out I sounded like a robot reading from a script (who knew?) Then one night, after getting yet another rejection email, I knew I needed to change my strategy. I started using ChatGPT not to write my answers, but to help me practice telling my own story. Today, these are my 10 go-to AI prompts to nail all of my interviews: 👉 1. Practice real mock interviews ↳ Get custom questions that actually match your target role, both technical and behavioral. 👉 2. Generate role-specific questions ↳ AI creates questions divided into technical, behavioral, and situational categories for YOUR specific job. 👉 3. Build STAR Stories that sound like you ↳ Structure your experiences using Situation, Task, Action, Result. Without sounding rehearsed. 👉 4. Turn your resume into stories ↳ Identify your key achievements and transform them into confident, results-driven narratives. 👉 5. Explain complex stuff simply ↳ Learn to break down technical concepts for both technical and non-technical interviewers. 👉 6. Get honest feedback on your answers ↳ AI evaluates your tone, clarity, and structure, then helps you sound more natural and confident. 👉 7. Master the HR and behavioral rounds ↳ Test your emotional intelligence and communication for those culture-fit conversations. 👉 8. Create your personal 7-day prep plan ↳ Build a daily routine with mock questions, review topics, and reflection exercises. 👉 9. Customize Answers for Each Company Align your responses with specific company values, mission, and role expectations. 👉 10. Nail "Tell Me About Yourself" ↳ Craft an intro that connects your journey, skills, and goals to the role, in under 2 minutes. Interview prep isn't about having perfect answers memorized. It's about knowing your story so well that you can tell it naturally, no matter how they ask the question. ChatGPT should be your practice partner, not your scriptwriter. Try these prompts before your next interview. You might surprise yourself with how prepared you actually are 👏 ♻️ Reshare this for someone prepping for interviews and follow me for more AI and career tips!

My Microsoft 𝗜𝗻𝘁𝗲𝗿𝘃𝗶𝗲𝘄 𝗘𝘅𝗽𝗲𝗿𝗶𝗲𝗻𝗰𝗲 for Software Engineer✨ I had the opportunity to interview with Microsoft, and I would like to share my comprehensive experience, which consisted of Online Assessment and Virtual Interview rounds. 📍𝗥𝗼𝘂𝗻𝗱 𝟭: 𝗢𝗻𝗹𝗶𝗻𝗲 𝗔𝘀𝘀𝗲𝘀𝘀𝗺𝗲𝗻𝘁 The first round was an online assessment, which comprised two questions in total. One of the questions was based on dynamic programming and second question focused on map data structures both are of Leetcode medium level. 📍𝗥𝗼𝘂𝗻𝗱 𝟮: 𝗧𝗲𝗰𝗵𝗻𝗶𝗰𝗮𝗹 𝗜𝗻𝘁𝗲𝗿𝘃𝗶𝗲𝘄 The second round was conducted by a Senior Software Engineer. He presented me with a coding question centered around graph data structures (LC medium-hard), specifically targeting the shortest path algorithm. The problem further included some additional constraints like some nodes are banned and source to destination distance via specific nodes, he further asked me about dynamic and static memory allocation. 📍𝗥𝗼𝘂𝗻𝗱 𝟯: 𝗧𝗲𝗰𝗵𝗻𝗶𝗰𝗮𝗹 𝗜𝗻𝘁𝗲𝗿𝘃𝗶𝗲𝘄 The third round was managed by an Engineering Manager. This interview began with a casual conversation about online multiplayer games, a topic I had mentioned in my introduction. This discussion served as an excellent icebreaker and set a comfortable tone for the rest of the interview. The manager then focused entirely on my resume, rigorously questioning me about my experiences and skills in React, C++, JavaScript, Socket.io and other technologies. Additionally, he asked questions related to Operating Systems and Object-Oriented Programming (OOP). In the Operating Systems segment, he inquired about deadlock, virtual memory and semaphores. Further he tested my understanding of the four pillars of Object-Oriented Programming. The interview concluded on a very positive note. 📍𝗥𝗼𝘂𝗻𝗱 𝟰: 𝗛𝗥 + 𝗧𝗲𝗰𝗵𝗻𝗶𝗰𝗮𝗹 𝗜𝗻𝘁𝗲𝗿𝘃𝗶𝗲𝘄 The final round was conducted by the Principal Software Eng Manager. Contrary to my expectations of a more managerial or HR-focused discussion, this interview was heavily technical. It began with an HR question, "Why do you want to join Microsoft?" for which I was well-prepared. Following this, he asked me a DSA question based on map and two pointers (LC medium). It took me some minutes to solve this question, during which we discussed its time and space complexity. To my surprise, he presented another DSA question, this time based on tree data structures. This was the most challenging question I had encountered in any interview (LC hard). Initially, the problem was somewhat unclear to me, so I asked about some constraints and clarified my doubts. Once my questions were addressed, I attempted a brute force approach, which did not satisfy him. After careful consideration, I devised a solution with logarithmic time complexity. This strategic approach turned out to be a pivotal moment, as he was highly impressed with my solution. #Microsoft #SoftwareEngineer #InterviewExperience #DSA