Walmart Global Tech India - Software Engineer
Interview Process
DSA & Problem Solving Round
The round started with a brief introduction where the interviewer asked about my previous experience, current responsibilities, projects, and technology stack.
After the introduction, the discussion moved to coding and problem-solving questions.
Questions Asked:
- Rearrange Array Such That A[i] = i
Rearrange an array so that each index contains its own value. If the corresponding value is not present, place -1 at that index. Discussion focused on efficient in-place solutions and time complexity.
- Binary Tree Problem Using BFS
Solve a binary tree problem using Breadth First Search. Discussed traversal strategy and implementation details.
- N-Queens Problem
Explain the complete approach. Write pseudocode for the solution. Discuss recursion, backtracking, and pruning techniques. Skills Evaluated: Data Structures & Algorithms Problem Solving Binary Trees BFS Recursion Backtracking Round Outcome:
Cleared the round and received confirmation within approximately 30 minutes.
Java & Data Structures Round
This round primarily focused on Java fundamentals, core computer science concepts, and implementation-based questions.
Questions Asked:
- Implement Queue Using Stack
Write complete working code. Explain the logic and time complexity.
- Internal Working of HashMap
How hashing works. Bucket structure. Collision handling. Performance characteristics.
- ArrayList vs LinkedList Scenario:
An application receives data in batches of 100 records. Which data structure would be preferred and why?
Discussion focused on:
Memory consumption Access speed Insert/Delete operations Practical trade-offs
- Singleton vs Static
Explain differences between Singleton and Static. When should each be used? Advantages and disadvantages. Real-world use cases.
This was one of the most challenging discussions during the interview.
Skills Evaluated: Core Java OOP Concepts Java Collections Framework Design Patterns Problem Solving Round Outcome:
Successfully cleared the round and progressed to the final stage.
Hiring Manager Round (System Design + Behavioral)
This was the most comprehensive round and covered system design, coding, architecture discussions, and behavioral questions.
System Design Question
Design a Music Streaming Application (Spotify / Prime Music)
Discussion Areas:
Functional Requirements Non-Functional Requirements High-Level Design Service Architecture Database Design APIs Scalability User Management Music Streaming Flow
The interviewer expected a structured approach to system design rather than a perfect solution.
Coding Question
Binary Tree Zig-Zag Traversal
Explain the approach. Write the solution. Discuss complexity analysis. Project Discussion
The interviewer spent considerable time understanding my current project.
Topics Included:
System Architecture Major Components Responsibilities Technical Challenges Design Decisions Optimizations Implemented Behavioral Questions
- What is the most complex problem you have solved?
Expected focus:
Ownership Problem-solving approach Impact
- What do you do daily to improve as an engineer?
Expected focus:
Learning mindset Continuous improvement Technical growth Skills Evaluated: System Design Software Architecture Communication Skills Leadership Potential Project Understanding Round Outcome:
Successfully cleared the final round and received an offer.
Detailed Experience & Tips
My interview process at Walmart Global Tech India consisted of three elimination rounds focusing on data structures, algorithms, Java fundamentals, system design, and behavioral skills.
The first round was heavily focused on problem-solving and DSA. Questions covered arrays, binary trees, BFS, and backtracking. Strong fundamentals in algorithms were essential to perform well.
The second round evaluated Java expertise and understanding of core computer science concepts. Topics such as Queue implementation using Stack, HashMap internals, ArrayList vs LinkedList trade-offs, and Singleton vs Static concepts were discussed in depth. Interviewers were interested not only in correct answers but also in reasoning and decision-making ability.
The final Hiring Manager round focused on system design and behavioral assessment. I was asked to design a music streaming application similar to Spotify and discuss architecture, APIs, databases, and scalability. The interviewer also explored my project experience and asked several behavioral questions to evaluate communication skills, ownership, and growth mindset.
Overall, the interview experience was positive and interviewer-friendly. Walmart looks for candidates with strong DSA fundamentals, good understanding of programming concepts, practical system design knowledge, and clear communication skills.
Preparation Tips
Practice medium and hard DSA problems regularly. Master Binary Trees, BFS, DFS, Recursion, and Backtracking. Understand Java Collections Framework thoroughly. Learn HashMap internals and common design patterns. Prepare at least one end-to-end system design problem. Be ready to explain your current project architecture in detail. Prepare behavioral examples demonstrating ownership and impact.