Airtel X Labs Internship Interview Experience 2020


Complete Process

There was a CGPA shortlisting of the applicants first, with a rather high cut off. 

There was an online round followed by 1 technical interview. 

Online Round 

There were 3 sections in the test, the first two being aptitude based and one being the coding section. Aptitude sections had to be solved quickly, so time was of the essence. 

One of the coding questions was based on greedy algorithms and the other one was on the sliding window method. 

Interview Round 

There was only one interview round for interns. It was a technical round and mostly revolved around questions from Data Structures and algorithms. 

I was asked 4 questions, which I had to code during the interview on google docs. 

The questions were: 

  1. Given an array A of non-negative integers, find a subarray which adds to a given number S.
  2. Given a sorted array of positive integers. Rearrange  the array elements alternatively i.e first element should be max value, second should be min value, third should be second max, fourth should be second min and so on…
  3. Postfix to Infix conversion
  4. Given a binary tree, find the maximum possible sum from one leaf node to another.

Apart from writing code, I also had to dry-run the codes on examples given by the interviewer.

The interviewer then asked a few questions based on OOP concepts and DBMS. 

The interviewer was fairly impressed, and I was selected, along with 5 others. 


  1. Maintaining a good CGPA is a must. 
  2. Practice coding questions from standard platforms, such as Leetcode, Interviewbit and so on. 
  3. It is also favorable to practice some of the aptitude questions, as quite a few of the companies ask these. They are easy questions, however, solving them correctly in a short amount of time is pretty challenging.
  4. Luck plays an important role in the whole process. It is fairly natural to be disheartened after a few rejections. Airtel was the fourth company I sat for interviews in, and after sitting in a total of 5 interviews, I was confident in this one, so, look at the rejections as stories to learn from.