Airtel

Role: SDE (Intern+FTE)

College: Not Specified

Interview Date: 2021

Interview Type: On-Campus

Result: Selected

Difficulty: Easy-Medium

Rounds: 3 rounds

Topics Asked: MCQs, Coding (design Linked List, implement Stack using Linked List, implement Queue using Stack, swap Kth node from beginning with Kth node from end in a Linked List), Projects, Event Loop in JS, Asynchronous JS, Networking, Abstract class in OOPS, HR questions.

Experience:

The process started with an Online Assessment consisting of MCQs and 2 coding questions of easy-medium difficulty. The candidate was able to solve both and was shortlisted.

Interview Round 1 (60-minutes)
The interviewer began with introductions and a discussion about the candidate's projects, including asking for URLs. This discussion lasted about 20 minutes. Following this, coding questions were asked: design a Linked List with basic operations (add, delete), implement a Stack using the designed Linked List (Push and Pop), and then implement a Queue using that Stack (enqueue and dequeue). The candidate first provided an O(N) approach for the Queue and then optimized it, satisfying the interviewer. The interviewer was friendly, making it feel more like a discussion.

Interview Round 2 (45-50 minutes)
This round also started with introductions and a quick discussion on projects. The interviewer asked about the Event Loop in JavaScript and how JS works asynchronously. A networking question was asked, which the candidate struggled with, admitting unfamiliarity with the topic. The interviewer then asked about abstract classes in OOPS. Finally, a coding question was given: "Swap Kth node from beginning with Kth node from end in a Linked List." The candidate explained the approach and wrote pseudo-code.

Interview Round 3 (15-minutes)
This was a brief HR round. The interviewer asked about the candidate's perception of Airtel's work and provided a link to an article to read and summarize within 5 minutes. The candidate advises keeping basics clean in DSA and tech stacks used in projects.