Walmart | SDE III | Bangalore | Interview Experience

I applied for the SDE III role at Walmart in Bangalore through a referral. My profile included a B.Tech from a Tier 1 college and 2.6 years of experience.

Round 1: Data Structures & Algorithms (DSA)

This round focused on coding. I was asked to find an element in a reverse sorted array, which I solved using binary search. The follow-up involved handling duplicate elements, and while I proposed some approaches, I couldn't implement an optimized solution on the spot. The second question was Course Schedule I, which I successfully solved using topological sort.

Round 2: Core Java

This round delved deep into Java concepts. I explained singleton classes, their real-life use cases, and wrote the code. We discussed keywords like final, static, and transient, though I wasn't familiar with transient at the time. I explained how to make a class immutable, error handling (checked vs. unchecked exceptions), and the nuances of empty catch blocks and their use in static methods (where I admit making a silly mistake). Deadlocks, their explanation, and prevention were also covered. A multithreading problem involved writing code to increment an attribute by two threads until it reached 5000. Further questions included AtomicInteger, the String pool, thread join, thread pool concepts, and the difference between Hashtable and ConcurrentHashMap. I was more prepared for HashMap vs. Hashtable and missed this specific difference. The interviewer was very supportive throughout.

Round 3: Hiring Manager (HM) Interview

This round, scheduled for an hour, concluded in 30 minutes. It started with questions related to my resume and a discussion on my current project. We touched upon threading and heap dump-related questions. A key discussion point was API optimization: how to optimize an API that makes multiple API calls, checks a cache, and finally queries the database. The behavioral question was about why I wanted to leave my current company. The round didn't go exactly as I had prepared for different topics, but the hiring manager was very chill, and fortunately, I received positive feedback.

Round 4: HR Interview

This round consisted of general behavioral questions. There was no discussion about compensation at this stage.

Outcome

I received the offer letter after 20 days. The offer was a bit low since I didn’t have any other competing offers, but I accepted it, though I plan to explore other opportunities.