Airtel X- Labs Software Development Engineer Interview Questions and Answers

Q1. About Insurance Domain Knowledge
Add your answer

Q1. About shift / Working hrs / Salary
Add your answer

Round duration - 90 minutes
Round difficulty - Medium

Q1. 
Rotate Matrix Right K Times
You are given a matrix MAT of size 'N' * 'M', where 'N' is the number of rows and 'M' is the number of columns, along with a positive integer 'K'. Your task is to rotate the ma...read more
Ans. 
Rotate a matrix to the right 'K' times by shifting each column to the right 'K' times.
• Iterate 'K' times to perform right rotation on the matrix

• Shift each column to the right by one position in each rotation

• Handle wrapping around the matrix when shifting columns

• Return the matrix elements row-wise after 'K' rotations
Answered by AI
Add your answer
Q2. 
Word Search Problem Statement
Given a two-dimensional grid of size N x M consisting of upper case characters and a string 'WORD', determine how many times the 'WORD' appears in the grid.
The 'WORD' can b...read more
Ans. 
Count how many times a given word appears in a 2D grid by moving in any of the eight possible directions.
• Iterate through each cell in the grid and check if the word can be formed starting from that cell in any of the eight directions.

• Use recursion to explore all possible paths from a starting cell to form the word.

• Keep track of visited cells to avoid revisiting the same cell in the same path.

• Return the count of how man
Answered by AI
Add your answer

Round duration - 75 minutes
Round difficulty - Medium

Interview started with an introduction and walk through the resume for first 5 minutes. After that, interview asked few coding questions.

Q1. 
Problem Statement: Largest Island
You are provided with a non-empty grid consisting of only 0s and 1s. Your task is to determine the maximum area of an island within the given grid.
An island consists of a...read more
Ans. 
Find the maximum area of an island in a grid of 0s and 1s.
• Iterate through the grid and perform depth-first search (DFS) to find connected 1s.

• Keep track of the area of each island found and return the maximum area.

• Consider all four directions (horizontal, vertical, and diagonal) while exploring the island.

• Handle edge cases like grid boundaries and already visited cells during DFS.

• If no island is present, return 0 as the
Answered by AI
Add your answer
Q2. 
Pythagorean Triplet Problem
Determine if there exists a Pythagorean triplet within a given array of integers. A Pythagorean triplet consists of three numbers, x, y, and z, such that x^2 + y^2 = z^2.
Expl...read more
Ans. 
Check if there exists a Pythagorean triplet in a given array of integers.
• Iterate through all possible triplets in the array and check if they form a Pythagorean triplet.

• Use a nested loop to generate all possible combinations of three numbers from the array.

• Check if the sum of squares of two numbers is equal to the square of the third number.
Answered by AI
Add your answer
Q3. 
Top View of Binary Tree Problem Statement
Given a Binary Tree of integers, you are tasked with finding the top view of the binary tree. The top view is the set of nodes visible when the tree is viewed fro...read more
Ans. 
Find the top view of a Binary Tree by returning a list of visible nodes when viewed from the top.
• Traverse the Binary Tree in level order and keep track of the horizontal distance of each node from the root.

• Use a map to store the nodes at each horizontal distance, and only keep the topmost node for each horizontal distance.

• Return the values of the topmost nodes in the map as the top view of the Binary Tree.
Answered by AI
Add your answer

Round duration - 90 minutes
Round difficulty - Medium

This round was focused on DSA along with short discussion on computer science fundamentals. For coding problems, I was asked to code the first problem only. For others, had to discuss the approach only. For computer science fundamentals, discussion on OOPS. Differences between process and threads were discussed.

Q1. 
Fixing a Swapped Binary Search Tree
Given a Binary Search Tree (BST) where two nodes have been swapped by mistake, your task is to restore or fix the BST without changing its structure.
Input:
The first...read more
Ans. 
Restore a Binary Search Tree by fixing two swapped nodes without changing its structure.
• Identify the two nodes that are swapped by mistake in the BST.

• Swap the values of the two identified nodes to restore the BST.

• Perform an in-order traversal of the BST to verify the correct restoration.

• Ensure no extra space other than the recursion stack is used for the solution.
Answered by AI
Add your answer
Q2. 
Implement Stack with Linked List
Your task is to implement a Stack data structure using a Singly Linked List.
Explanation:
Create a class named Stack which supports the following operations, each in O(1...read more
Ans. 
Implement a Stack data structure using a Singly Linked List with operations like getSize, isEmpty, push, pop, and getTop in O(1) time.
• Create a class named Stack with methods for getSize, isEmpty, push, pop, and getTop.

• Use a Singly Linked List to store the elements of the stack.

• Ensure that each operation runs in constant time O(1).

• Handle edge cases like empty stack appropriately.

• Test the implementation with sample queri
Answered by AI
Add your answer

Round duration - 45 Minutes
Round difficulty - Medium

Q1. Design a class booking application for students.
Ans. 
A class booking application for students to schedule and manage their classes.
• Create a class booking system where students can view available classes, book classes, and manage their schedule.

• Include features like class search, class details, booking confirmation, and calendar view.

• Implement user authentication to ensure only registered students can book classes.

• Allow students to cancel or reschedule classes with proper...read more
Answered by AI
Add your answer

Round duration - 60 Minutes
Round difficulty - Medium

The interviewer understand the current problem statement I was working on. 
Asked the clarifying questions and alternative approaches to solve the same and their tradeoffs.
Also, asked about the technologies I was using in depth and reason for choosing the same.

Q1. 
Gas Tank Problem Statement
You have a car with a gas tank of infinite capacity. There are 'N' gas stations located along a circular route, numbered from 0 to N-1. You begin your journey with an empty tank...read more
Ans. 
Find the starting gas station index to complete a circular route with gas and cost arrays.
• Iterate through gas stations, keeping track of gas remaining after each station

• If gas remaining is negative, reset starting station to current station + 1

• If total gas remaining at the end is greater than or equal to total cost, return starting station index
Answered by AI
Add your answer

Round duration - 45 Minutes
Round difficulty - Medium

This round was their with the CTO and was mostly the culture fitment round.

Round duration - 30 Minutes
Round difficulty - Easy

This round was with the cofounder and was mostly culture fitment.

2 coding questions (1 DP + 1 Graph)

Q1. Leetcode easy, medium questions on tree, dp
Add your answer

Q1. 1 coding question on string (hard).
Add your answer
Q2. OS, DBMS, OOPs questions
Add your answer

Q1. Usual HR questions + 2 puzzles question
Add your answer