Walmart SWE III Interview Experience | India
Summary
I interviewed for a SWE III role at Walmart in India, which involved three rounds covering Data Structures & Algorithms, Low-Level Design and core Java, and behavioral questions. Following the interviews, I received a request for document submission.
Full Experience
Education: BE from State University Work Experience: 2.9 Years (SDE 1)
I had applied to multiple openings via Google Forms shared on LinkedIn. A recruiter reached out to me and asked if I could attend in-office interviews on 21/03 (Friday).
Round 1
This round was DSA-focused, and I was expected to code in Java.
- A variation of the max sum subarray problem.
- Valid Parentheses.
Round 2
This round was a mix of LLD and core Java concepts. It started with an LLD problem, and the discussion went on for ~35 minutes, followed by Java-related questions.
- Design LLD for a digital wallet. Users should be able to create an account, manage personal info, and have different payment methods. Funds can be transferred between wallets and banks as well. Users should be able to see transaction history.
- Garbage collection in Java.
- Multithreading concepts.
- Threadpool, stringpool
Round 3 (HM Round)
This was supposed to be conducted on the same day, but due to unavailability, it happened on Tuesday. It mostly included behavioral and Java-related questions.
- Questions based on my resume, college, etc.
- If your manager has a different approach to solving a problem than yours, what would you do? Similar behavioral questions—don’t exactly remember the others.
- Dynamic dispatch in java
- Null pointer exception. Asked me to create one
- Differences between Java 8 and Java 17.
- Different primitive data types in Java with their sizes.
- How multithreading is achieved in Java.
Got a mail regarding document submission next day. No verbal/official offer from HR.
Interview Questions (11)
Determine if the input string is valid. An input string is valid if: Open brackets must be closed by the same type of brackets. Open brackets must be closed in the correct order. Every close bracket has a corresponding open bracket of the same type.
Design the low-level components for a digital wallet system. Users should be able to create an account, manage personal information, and link various payment methods. The system should support fund transfers between different wallets and between wallets and banks. Additionally, users must be able to view their transaction history.
Explain the concept of garbage collection in Java, how it works, and its various algorithms.
Discuss fundamental multithreading concepts in Java, including thread creation, synchronization, and inter-thread communication.
Explain the concepts of Thread Pool and String Pool in Java, their uses, and internal workings.
If your manager proposes an approach to solving a problem that differs from yours, how would you handle the situation?
Explain dynamic dispatch in Java, how it works, and provide an example.
Explain what a Null Pointer Exception (NPE) is in Java and demonstrate how to intentionally create one.
Describe the key differences and new features introduced between Java 8 and Java 17.
List and explain the different primitive data types available in Java, along with their respective memory sizes.
Explain the mechanisms and approaches to achieve multithreading in Java.