Airtel Xlabs Interview Experience

Airtel Xlabs came to our campus to hire for the position of Engineering leads at Airtel. The CGPA cutoff for the online test is above 7.5 and around 200 students shortlisted for the Online test.

Round 1(Online Test - 90 minutes): The online test consists of two sections,

Section 1: It is again divided into two subsections consisting of 14 and 16 aptitude questions to be completed in 30 minutes, and I strongly recommend to practice aptitude questions from India Bix and GFG.

Section 2: It consists of two coding questions to be completed in 60 minutes and the questions are of medium difficulty The questions are

1. Given two different races of rats and one race gives birth to three children in the first year and two children in the second year and dies in the third year and another race gives birth to three children in the first year and dies in the second year given their initial population find their population after N years.
2. And the second question is given the numbers in an array and the number signifies how many times a shopkeeper can sell in a particular city, and he shouldn't visit the same cities on two consecutive days We need to find how many days the shopkeeper can sell his goods in different cities.

Round 2(Technical interview): The interviewer gave me a quick introduction about himself and asked me to introduce myself. Then we had a discussion on my project which was based on machine learning and thereafter he asked me some questions on oops

1. The difference between abstract class and interfaces, and he was very keen on why can't we achieve 100 percent abstraction using abstract class.
2. The difference between method overloading and method overriding, and he gave me different instances and asked me which method would be called

Then he asked me two coding questions which were 

1. Merge two sorted arrays in linear time using constant space 
2. Return second last node from the linked list and our code needs to handle all the corner cases

Then he asked if I had any questions for him and I asked him about his role at Airtel  and some questions about the company 

Round 3(Technical interview): I was selected for round 2 and the interviewer asked me my favourite coding language for which I replied C++, then he asked me the reason for the segmentation fault in C++.

Then he gave me a coding question, and we are given N line segments on X-axis and we need to find the common lengths of all line segments, and we can delete at most one line segment to maximize the intersection length, and we have to return the maximum intersection length.

We are given a 2D array sorted row-wise and column-wise, and we need to design a searching algorithm to find whether an element exists in an array or not.

We are given an array and a value K, and we need to find no of triplets with sum K exists in the array.

Then he asked me about the difference between normalization and demoralization and given a real-life problem at Airtel and asked me to design a database for it 

Round 4 (HR interview): This round consists of basic HR questions like What are your hobbies, What are your strengths, Why we should we hire you  and then the HR finally announced that I was selected for a full-time role  at Airtel and that was one of the best moment of my life  

Thanks to GeeksforGeeks,  InterviewBit, and LeetCode for helping me in my preparation.

Thank you