30+ Lumax Industries Interview Questions and Answers

Use a max heap to keep track of the K largest elements in a continuous stream of integers.

• Create a max heap of size K to store the K largest elements.

• For each new element in the stream, compare it with the root of the max heap. If it is larger, replace the root with the new element and heapify.

• At any point, the root of the max heap will be the Kth largest element in the stream.

Use sliding window technique to find minimum window in s containing all characters of t.

• Use two pointers to create a window in s

• Move the right pointer to expand the window until all characters of t are found

• Move the left pointer to shrink the window while maintaining all characters of t

• Update minimum window size as you iterate through s

The minimum number of coins required to express a given amount of money is calculated using a dynamic programming approach.

• Use dynamic programming to calculate the minimum number of coins required for each amount from 1 to the given amount.

• Start with the base case of 0 coins required for amount 0, then iterate through each coin type to calculate the minimum coins required for each amount.

• Choose the minimum of the current minimum coins required and the minimum coins required f...read more

Program to find longest consecutive sequence and length of longest path in a binary tree.

• Traverse the binary tree using depth-first search (DFS)

• Keep track of the current consecutive sequence length and the longest consecutive sequence found so far

• Update the length of the longest path as you traverse the tree

Program to find lowest common ancestor of two nodes in a binary tree with unique values.

• Start from the root and traverse the tree to find the paths from root to the two nodes.

• Compare the paths to find the lowest common ancestor node.

• Use recursion to traverse the tree efficiently.

• Handle edge cases like if one of the nodes is the ancestor of the other.

Return the next lexicographically greater permutation of a given sequence or return it in ascending order if not possible.

• Use the concept of lexicographic ordering to find the next permutation.

• If the sequence is already in descending order, return it in ascending order.

• Examples: ['a', 'b', 'c'] -> ['a', 'c', 'b'], ['3', '2', '1'] -> ['1', '2', '3']

Convert a set of integers to Roman numerals

• Create a function that takes an integer array as input

• Use a loop to iterate through each integer and convert it to Roman numeral

• Implement a mapping of integers to Roman numerals for conversion

• Return an array of strings containing the Roman numeral equivalents

Find all palindromic decompositions of a given string s.

• Iterate through all possible substrings and check if they are palindromes.

• Use backtracking to generate all possible decompositions.

• Return the list of palindromic decompositions.

Autocomplete feature for a search engine

• 1. Display suggestions as user types in the search bar

• 2. Suggestions should be based on popular searches or previous searches

• 3. Allow users to select a suggestion to complete their search

• 4. Update suggestions in real-time as the user continues typing

A customer relationship management platform for Comcast would focus on personalized customer interactions and efficient issue resolution.

• Implement a centralized database to store customer information and interaction history.

• Integrate communication channels such as phone, email, and chat for seamless customer support.

• Utilize data analytics to track customer behavior and preferences for targeted marketing campaigns.

• Automate processes for issue resolution and follow-up to improv...read more

A ticketing management system for a theatre to streamline ticket sales and seat allocation.

• Create an online platform for customers to purchase tickets

• Implement a seating chart to allow customers to select their seats

• Include options for different ticket types (e.g. VIP, standard, student)

• Generate electronic tickets for customers to present at the theatre entrance

• Integrate payment processing for secure transactions

Design a home monitoring system for Comcast.

• Include smart sensors for monitoring temperature, humidity, and motion

• Integrate with smart devices like thermostats, cameras, and door locks

• Provide real-time alerts and notifications to homeowners via mobile app

• Allow remote access and control of home devices

• Offer optional professional monitoring services for added security

Dependency injection is a design pattern that allows objects to receive dependencies rather than creating them.

• Dependency injection is a way to achieve loose coupling between objects.

• It allows for easier testing and maintenance of code.

• There are three types of dependency injection: constructor injection, setter injection, and interface injection.

• Inversion of control is a principle that states that the control of object creation and lifecycle should be handed over to a contain...read more

Horizontal scaling is adding more machines to your pool of resources, while vertical scaling is adding more power (CPU, RAM) to an existing machine.

• Use horizontal scaling when you need to increase capacity by adding more machines to distribute the load.

• Use vertical scaling when you need to handle increased load on a single machine by adding more resources like CPU or RAM.

• Horizontal scaling is more cost-effective and provides better fault tolerance.

• Vertical scaling is easier t...read more

Git stash is a command in Git that temporarily shelves changes so you can work on something else.

• Git stash is used to save changes that are not ready to be committed yet.

• It allows you to switch branches without committing changes.

• Conflicts can occur when stashed changes conflict with changes in the current branch.

• You can resolve conflicts by applying the stash, resolving conflicts, and then committing the changes.

Unit testing is a software testing method where individual units or components of a software are tested in isolation.

• Unit testing is typically done by developers to ensure that each unit of code functions correctly on its own.

• It helps in identifying bugs early in the development process.

• Unit tests are automated and focus on testing small, specific parts of the code.

• Examples of unit testing frameworks include JUnit for Java, NUnit for .NET, and pytest for Python.

Use Python in Robot Framework to generate random mobile numbers for 10 users.

• Use the Faker library in Python to generate random mobile numbers

• Create a loop to generate mobile numbers for 10 users

• Implement the logic in a Robot Framework test case

Efficient in using GitHub and command line tools for version control and automation.

• Proficient in using Git commands for version control and collaboration.

• Familiar with creating branches, merging code, resolving conflicts, and managing repositories on GitHub.

• Experienced in using command line tools for automation tasks like scripting and deployment.

• Comfortable with tools like Git Bash, Git GUI, and command line interfaces for various operating systems.

I prioritize items based on business value and work with the team to refine and estimate them.

• Collaborate with team to ensure understanding of user stories

• Prioritize backlog items based on business value and user needs

• Refine backlog items to ensure they are clear, concise, and actionable

• Estimate backlog items with the team to ensure feasibility and accuracy

Inheritance is a mechanism in object-oriented programming where a class inherits properties and behaviors from another class. Implementation is the process of defining the methods and behaviors of a class.

• Inheritance allows a class to inherit attributes and methods from another class, promoting code reusability.

• Implementation involves writing the actual code for the methods and behaviors defined in a class.

• Example: Class 'Animal' can be a base class with attributes like 'name...read more

The method to be redefined for post call is 'PROCESS_AFTER_INPUT'.

• The method 'PROCESS_AFTER_INPUT' is used to process data after user input in a screen.

• It is commonly redefined in SAP ABAP programs to perform validations or calculations based on user input.

• Example: Redefining 'PROCESS_AFTER_INPUT' method in a custom screen program to validate user input before saving data.

To check system status in OS level, use commands like top, ps, vmstat, sar, etc.

• Use 'top' command to display real-time system information like CPU and memory usage

• Use 'ps' command to display currently running processes

• Use 'vmstat' command to display virtual memory statistics

• Use 'sar' command to display system activity reports

Response codes in API testing indicate the status of the request made to the API.

• 200 - OK: Request was successful

• 400 - Bad Request: Invalid input or missing parameters

• 401 - Unauthorized: Authentication required

• 404 - Not Found: Resource not found

• 500 - Internal Server Error: Server-side issue

HR BP team uses various metrics to measure employee performance and engagement.

• Employee turnover rate

• Absenteeism rate

• Time to fill vacancies

• Training and development metrics

• Employee satisfaction surveys

• Diversity and inclusion metrics

Program to calculate the sum of digits in a number

• Iterate through each digit of the number and add them together

• Use modulus operator to extract each digit

• Convert the number to a string to easily access individual digits

Windows logs are stored in the Event Viewer application on Windows operating systems.

• Windows logs are stored in the Event Viewer application.

• Event Viewer can be accessed by searching for 'Event Viewer' in the Windows search bar.

• Logs are categorized into different sections such as Application, Security, System, etc.

Use C++ to write an input stream to a file.

• Open the input stream and output file streams in C++.

• Read from the input stream and write to the output file stream.

• Close both streams after writing is complete.

Severity is the impact of a bug on the system, while priority is the urgency of fixing it.

• Severity is the measure of how much a bug affects the system's functionality.

• Priority is the order in which bugs should be fixed based on urgency.

• Severity is usually categorized as low, medium, or high.

• Priority is usually categorized as low, medium, or high.

• For example, a bug that causes the system to crash would have high severity and high priority.

Find the smallest number in an array of strings

• Convert the strings to numbers before comparing

• Use a loop to iterate through the array and keep track of the smallest number

• Handle cases where the array is empty or contains non-numeric strings

• Example: ['5', '10', '2', '8'] should return '2'

Post call is made after a transaction is completed, while patch call is used to update specific parts of a resource.

• Post call creates a new resource, while patch call updates an existing resource.

• Post call is used for creating new records in a database, while patch call is used for updating existing records.

• Post call is idempotent, meaning multiple identical requests will have the same effect, while patch call is not necessarily idempotent.

Count the number of times a specific substring appears in a given string.

• Use a loop to iterate through the string and check for the substring at each position.

• Use a counter variable to keep track of the number of times the substring is found.

• Consider using built-in string functions or regular expressions for efficient counting.

• Example: Given string 'hellohellohello' and substring 'hello', the count would be 3.

A data warehouse is a centralized repository that stores structured and unstructured data from various sources for analysis and reporting.

• Data warehouses are used for decision-making and business intelligence purposes.

• They typically involve extracting, transforming, and loading data from different sources into a single, unified database.

• Data warehouses often use dimensional modeling and OLAP (Online Analytical Processing) techniques.

• Examples of data warehouse tools include Sn...read more

Facts are measurable data points, while dimensions provide context to the facts.

• Facts are quantitative data that can be measured or counted.

• Dimensions are qualitative data that provide context to the facts.

• Examples: In a sales database, sales amount is a fact, while product category is a dimension.

The project structure includes folders for source code, test scripts, configuration files, and documentation.

• Main folders: src (source code), test (test scripts), config (configuration files), docs (documentation)

• Subfolders: src/main/java (Java source code), src/test/java (test scripts), config/env (environment configurations)

• Build tools: Maven, Gradle

• Version control: Git

• Continuous integration: Jenkins, Travis CI

Our framework is a hybrid framework that uses both data-driven and keyword-driven approaches.

• Our framework is built using Selenium WebDriver and TestNG.

• It uses Excel sheets to store test data and Apache POI library to read/write data from/to Excel.

• We have created custom keywords for common actions like clicking, entering text, etc.

• We have also implemented page object model for better organization and maintenance of code.

• Our framework generates detailed HTML reports using Exte...read more

TLS handshake is a process of establishing a secure connection between a client and a server.

• TLS handshake involves a series of steps such as client hello, server hello, certificate exchange, key exchange, and session establishment.

• During the handshake, the client and server negotiate the encryption algorithm and exchange keys to encrypt and decrypt data.

• TLS handshake ensures the authenticity, confidentiality, and integrity of the communication between the client and server.

• I...read more

Oracle architecture is a multi-tiered system with components like client, server, and database.

• Oracle architecture consists of client, server, and database components.

• The client communicates with the server to access the database.

• The server processes the client's requests and interacts with the database.

• The database stores and manages the data.

• Oracle architecture is designed to be scalable and secure.

DRM stands for Digital Rights Management, a technology used to protect digital content from unauthorized access and distribution.

• DRM is used to control access to digital content and prevent piracy.

• It can restrict the number of devices a user can access the content on.

• DRM can also limit the ability to copy, print, or share digital content.

• Examples of DRM include encrypted eBooks, streaming services like Netflix, and software with license keys.