WebMD Node JS Developer Interview Questions and Answers

Round duration - 60 minutes
Round difficulty - Medium

30 Aptitude problems and two coding questions

Q1. 
Count Inversions Problem Statement
Given an integer array ARR of size N, your task is to find the total number of inversions that exist in the array.
An inversion is defined for a pair of integers in the...read more
Ans. 
Count the total number of inversions in an integer array.
• Iterate through the array and for each pair of elements, check if the conditions for inversion are met.

• Use a nested loop to compare each pair of elements efficiently.

• Keep a count of the inversions found and return the total count at the end.
Answered by AI
Add your answer
Q2. 
Maximum Subarray Sum Problem Statement
Given an array of integers, determine the maximum possible sum of any contiguous subarray within the array.
Example:
Input:
array = [34, -50, 42, 14, -5, 86]
Out...read more
Ans. 
Find the maximum sum of any contiguous subarray within an array of integers.
• Iterate through the array and keep track of the maximum sum of subarrays encountered so far.

• At each index, decide whether to include the current element in the subarray or start a new subarray.

• Use Kadane's algorithm to solve the problem efficiently.

• Example: For array [34, -50, 42, 14, -5, 86], the maximum subarray sum is 137.
Answered by AI
Add your answer

Round duration - 90 minutes
Round difficulty - Medium

Data structure and algorithms plus object oriented problems

Q1. 
Merge Sort Problem Statement
You are given a sequence of numbers, ARR. Your task is to return a sorted sequence of ARR in non-descending order using the Merge Sort algorithm.
Explanation:
The Merge Sort...read more
Ans. 
Implement Merge Sort algorithm to sort a sequence of numbers in non-descending order.
• Divide the input array into two halves recursively until each array has only one element.

• Merge the sorted halves to produce a completely sorted array.

• Time complexity of Merge Sort is O(n log n).

• Example: Input: [3, 1, 4, 1, 5], Output: [1, 1, 3, 4, 5]
Answered by AI
Add your answer
Q2. 
Problem Statement: Delete Node In A Linked List
Given a singly linked list of integers and a reference to a node, your task is to delete that specific node from the linked list. Each node in the linked li...read more
Ans. 
Given a singly linked list of integers and a reference to a node, delete the specified node from the linked list.
• Traverse the linked list to find the node to be deleted

• Update the pointers to skip over the node to be deleted

• Print the modified linked list after deletion
Answered by AI
Add your answer

Round duration - 60 miinutes
Round difficulty - Easy

Database questions and discussion about projects

Q1. What is a normal form in database management systems, and can you explain Boyce-Codd Normal Form (BCNF)?
Ans. 
Normal forms in database management systems help in organizing data to reduce redundancy and improve data integrity.
• Normal forms are rules used to design relational database tables to minimize redundancy and dependency.

• Boyce-Codd Normal Form (BCNF) is a stricter version of Third Normal Form (3NF) where every determinant is a candidate key.

• BCNF helps in eliminating anomalies like insertion, update, and deletion anomalie...read more
Answered by AI
Add your answer
Q2. What is the difference between the 'WHILE' keyword and the 'HAVING' keyword in SQL?
Ans. 
WHILE is used in loops to repeatedly execute a block of code, while HAVING is used in SQL queries to filter results based on aggregate functions.
• WHILE is used in programming languages like SQL to create loops for executing a block of code multiple times.

• HAVING is used in SQL queries to filter results based on aggregate functions like SUM, COUNT, AVG, etc.

• WHILE is used for iterative operations, while HAVING is used for ...read more
Answered by AI
Add your answer

Q1. React hooks, Explain using code
Ans. 
React hooks are functions that let you use state and other React features without writing a class.
• Hooks are functions that let you use state and other React features in functional components

• useState() is a hook that allows you to add state to functional components

• useEffect() is a hook that allows you to perform side effects in functional components

• useContext() is a hook that allows you to use the context API in functio...read more
Answered by AI
Add your answer
Q2. Factory Patterns?
Add your answer
Q3. Liskov Substitution Principle
Ans. 
Liskov Substitution Principle states that objects of a superclass should be replaceable with objects of its subclasses without affecting the program's correctness.
• Subtypes must be substitutable for their base types.

• Derived classes must be able to replace their base classes without affecting the program's behavior.

• Violating this principle can lead to unexpected behavior and errors in the code.

• Example: If a program expec...read more
Answered by AI
Add your answer
Q4. Oops Concept and give examples
Ans. 
Oops concept is a programming paradigm that focuses on objects and classes.
• Oops stands for Object-Oriented Programming

• Key concepts include inheritance, encapsulation, polymorphism, and abstraction

• Examples: Class Car with properties like make, model, and methods like start(), stop()

• Example: Inheritance - Class SUV extends Car and adds property numSeats
Answered by AI
Add your answer
Q5. JQuery - Ajax mechanisms
Add your answer
Q6. Docker and Kubernetes - Azure concepts
Add your answer

Q1. Experience and self introduction
Add your answer

Q1. Oops related insharitance encapsulation
Ans. 
Inheritance and encapsulation are core OOP concepts that promote code reuse and data protection in software development.
• Inheritance allows a class to inherit properties and methods from another class, promoting code reuse. Example: class Dog extends Animal.

• Encapsulation restricts access to certain components of an object, protecting its state. Example: using private variables with public getters/setters.

• Inheritance can...read more
Answered by AI
Add your answer

Q1. Difference b/w full and partial selectors
Ans. 
Full selectors select all descendants of a specified element, while partial selectors select only direct children.
• Full selectors use a space between the parent and child elements, while partial selectors use the > symbol.

• Full selectors are more general and can target multiple levels of descendants, while partial selectors are more specific and target only direct children.

• Example of full selector: div p selects all

  ele...read more
Answered by AI
Add your answer
Q2. What is Screen scraping and data scraping
Ans. 
Screen scraping is extracting data from a website's HTML code, while data scraping is extracting data from various sources.
• Screen scraping involves extracting data from the visual representation of a website, usually using automation tools like web scrapers.

• Data scraping involves extracting data from various sources such as databases, APIs, and documents.

• Both screen scraping and data scraping are used to collect and an...read more
Answered by AI
Add your answer

It was medium to difficult level test

Q1. Questions about core subjects like oops pillars
Add your answer
Q2. Questions about projects, technologies used
Add your answer

Q1. Why do you want to join this
Add your answer
Q2. Your previous experience and questions about your background
Add your answer

Computer fundamentals

Q1. Technical questions of projects ,dsa
Add your answer

Q1. What is ur background
Add your answer
Q2. Manegarial and behavioral questions
Add your answer