The interview process consisted of an MCQ challenge with 25 DSA and CS fundamental questions, followed by a Coding Challenge round with 2 coding problems.
Technical Round 1: The first technical round lasted around 45-50 minutes. It began with introductions.
- I was asked to solve 4 DSA problems and write their codes on any IDE of my choice.
- Find the second largest element in an array in a single iteration without extra space.
- Find the length of the subarray with longest consecutive 1s in a binary array.
- Check whether the given strings are anagrams.
- How to insert and delete an element from a doubly linked list.
- SQL query to find the student with the most number of certifications.
- How to write (i) into an existing HTML element (ii) into the HTML output, using JavaScript?
- How do you create an object in Java?
- There is a class Shape and two sub-classes Rectangle and Circle who want to inherit the properties of Shape. How would you do that? Which type of access modifier is suitable?
- You are supposed to receive 25 guests, what is the time complexity of cleaning your room? What is the time complexity of greeting every guest? What is the time complexity of passing dinner to everyone? Every guest has to greet you and the other guests, what will be the time complexity?
The remaining questions were based on my resume project, related to JavaScript, Django, image processing, and DBMS.
Technical Round 2: This round also lasted 50 minutes. The first half involved solving a DSA problem (had to write code on an IDE) and the second half focused on core concepts and projects.
- There are 3 strings s1, s2 and s3. If s2 is present in s1, replace every occurrence of s2 in s1 by s3 (their lengths may be random). For example, if s1 = "she ran marathon", s2 = "ra", s3 = "non", expected output "she nonn manonthon".
- Difference between JDK and JRE. Which JDK version do you use?
- What is the static keyword in Java? What would happen if we write "public void main(String[] args) " instead of "public static void main(String[] args) "?
- Difference between interface and abstract keyword.
- What is the "this" keyword in Java? What is the "let" keyword?
- What is polymorphism?
- Difference between the operator "==" and ".equals() "?
- Syntax of lambda function.
- Name some frontend and backend technologies. Difference between Angular and React. How do frontend and backend communicate?
The round concluded with a brief discussion about my internship project.
Final Round (Hiring Manager): The final stage involved a 45-minute conversation with the Hiring Manager, where the emphasis shifted towards personal and behavioral aspects. We discussed my final year project, extracurricular activities, hypothetical scenarios, and my motivations for seeking employment at Walmart.