100+ Interview Questions and Answers

Reconstruct original sequence of cards given a specific sequence of cards placed on table.

• The last card placed on the table must be 10.

• The second last card placed on the table must be 5 or 6.

• The first card placed on the table must be either 1 or 2.

• Use trial and error method to reconstruct the original sequence.

Java function to return subnet mask of IP and URL after www.

• Read the file and store IP addresses and URLs in separate arrays

• Use regex to extract subnet mask from IP address

• Use substring to extract URL after www.

• Return subnet mask and URL as separate strings

For Snapdeal's shoe section, I would design a DBMS with separate entities for Sports and Casual Shoes.

• Create a main entity for shoes with attributes like brand, size, color, etc.

• Create separate entities for Sports and Casual Shoes with attributes specific to each category.

• Link the Sports and Casual Shoe entities to the main Shoe entity using a foreign key.

• Use indexing and normalization techniques to optimize performance and reduce redundancy.

• Consider implementing a search fea...read more

Burn one rope from both ends and the other rope from one end.

• Light one rope from both ends and the other rope from one end.

• When the first rope burns completely, 30 minutes have passed.

• Then, immediately light the other end of the second rope.

• When the second rope burns completely, 15 more minutes have passed.

• Total time elapsed is 45 minutes.

Merge two sorted arrays into one sorted array of larger size

• Create a new array of size m+n

• Compare the last elements of both arrays and insert the larger one at the end of the new array

• Repeat until all elements are merged

• If any elements are left in the smaller array, insert them at the beginning of the new array

• Time complexity: O(m+n)

• Example: arr1=[1,3,5,7,0,0,0], arr2=[2,4,6], output=[1,2,3,4,5,6,7]

The question asks to find the count of words in a dictionary that can be formed by a given number.

• Iterate through each word in the dictionary

• Check if the characters in the word can be formed using the given number

• Increment the count if the word can be formed

There are 6 colors, so 6^3 = 216 different cubes can be obtained.

• The cube has 6 faces, each of which can be one of 6 colors.

• Therefore, there are 6 options for the first face, 6 for the second, and 6 for the third.

• To find the total number of possible cubes, we multiply these options together: 6 x 6 x 6 = 216.

DNS servers translate domain names into IP addresses to enable communication between devices on the internet.

• DNS servers act as a phone book for the internet, translating domain names into IP addresses.

• When a user types a domain name into their browser, the browser sends a request to a DNS server to resolve the domain name into an IP address.

• DNS servers operate in a hierarchical system, with root servers at the top, followed by top-level domain servers, and then authoritative...read more

BookMyShow should charge different prices based on factors like movie of superstar, festival occasion, etc.

• Consider the popularity of the movie star

• Take into account the demand for tickets during festival occasions

• Analyze the competition and market trends

• Offer discounts for bulk bookings or loyalty programs

• Consider the cost of production and distribution

• Adjust prices based on the time of day or week

• Use dynamic pricing to optimize revenue

• Examples: Charge higher prices for a mo...read more

Defective pack elimination during transportation loading

• Inspect each pack before loading

• Use a checklist to ensure all packs are accounted for

• Separate defective packs from non-defective ones

• Label defective packs clearly

• Dispose of defective packs properly

• Train personnel on proper handling procedures

When dealing with a customer who is already upset with a previous executive, it is important to empathize, listen actively, apologize if necessary, and offer a solution or escalate the issue if needed.

• Empathize with the customer and acknowledge their frustration.

• Listen actively to understand their concerns and let them vent if necessary.

• Apologize for any inconvenience caused by the previous executive, even if it wasn't your fault.

• Offer a solution or alternative to address the...read more

Finding lowest common ancestor of two nodes in binary tree

• Traverse the tree from root to both nodes and store the paths in separate arrays

• Compare the paths to find the last common node

• Return the last common node as the lowest common ancestor

• Use recursion to traverse the tree efficiently

Code to find if input date is today/tomorrow or no of days difference from current date.

• Get current date using Date() constructor

• Convert input date to Date object

• Compare input date with current date to check if it's today/tomorrow

• If not, calculate the difference in days using getTime() method

• Output the result accordingly

Algorithm to find LCM of all numbers from 1 to n and its time complexity

• Find prime factors of all numbers from 1 to n

• For each prime factor, find the highest power it appears in any number from 1 to n

• Multiply all prime factors raised to their highest power to get LCM

• Time complexity: O(n*log(log(n)))

Box model defines how elements are rendered in CSS. Specificity determines which CSS rule applies to an element. Render-blocking statements delay page rendering.

• Box model includes content, padding, border, and margin.

• Specificity is calculated based on the number of selectors and their types.

• Render-blocking statements are CSS or JavaScript files that prevent the page from rendering until they are loaded.

• Use media queries to optimize rendering and reduce render-blocking stateme...read more

Calculate top 10 frequently used words on Facebook in 1 hour dynamically.

• Use Facebook API to fetch data

• Implement a script to count word frequency

• Sort the words based on frequency and return top 10

Event bubbling and event capturing are two mechanisms in JavaScript that describe the order in which events are handled.

• Event bubbling is the process where an event is first captured by the innermost element and then propagated to its parent elements.

• Event capturing is the opposite process where an event is first captured by the outermost element and then propagated to its child elements.

• Event bubbling is the default behavior in most browsers.

• Event.stopPropagation() can be us...read more

Implement infinite scrolling in React JS using Intersection Observer API.

• Use Intersection Observer API to detect when the user has scrolled to the bottom of the page.

• Fetch new data and append it to the existing data using setState.

• Use a loading spinner to indicate that new data is being fetched.

• Add a debounce function to prevent multiple API calls while scrolling.

• Use a key prop when rendering the list of data to avoid re-rendering of existing elements.

The number is 7744.

• The number must end in 00 or 44.

• The square root of the number must be a whole number.

• The only possible number is 7744.

To find the length of non-looped linked list, we need to traverse the list and count the number of nodes.

• Traverse the linked list using a pointer and count the number of nodes until the end of the list is reached.

• If a loop is encountered, break out of the loop and continue counting until the end of the list.

• Return the count as the length of the non-looped linked list.

Saas is a CSS preprocessor that extends the functionality of CSS with variables, mixins, and more.

• Saas stands for Syntactically Awesome Style Sheets

• It allows for the use of variables, mixins, and functions in CSS

• Saas code must be compiled into CSS before it can be used in a web page

• Saas is often used in conjunction with build tools like Gulp or Webpack

Inner join returns only the matching rows between two tables, while outer join returns all rows from one table and matching rows from the other.

• Inner join combines rows from two tables based on a matching column.

• Outer join returns all rows from one table and matching rows from the other.

• Left outer join returns all rows from the left table and matching rows from the right table.

• Right outer join returns all rows from the right table and matching rows from the left table.

• Full ou...read more

To find the merging point of two linked lists

• Traverse both linked lists and find their lengths

• Move the pointer of the longer list by the difference in lengths

• Traverse both lists simultaneously until they meet at the merging point

Snapdeal is a leading e-commerce company in India with a strong customer base and a wide range of products.

• Snapdeal has a large customer base in India, which provides a great opportunity for growth and impact.

• The company offers a wide range of products across various categories, catering to diverse customer needs.

• Snapdeal has a strong presence in the e-commerce market, competing with other major players.

• The company has a user-friendly platform and offers convenient payment op...read more

Code to check equality of two objects in JavaScript

• Use the JSON.stringify() method to convert the objects into strings

• Compare the string representations of the objects using the === operator

• If the strings are equal, the objects are considered equal

Codes for Post-Order, In-Order, and Level-Order Traversal of a binary tree.

• Post-Order Traversal: Left subtree, Right subtree, Root

• In-Order Traversal: Left subtree, Root, Right subtree

• Level-Order Traversal: Visit nodes level by level, from left to right

Bind creates a new function with a specified 'this' value and arguments.

• Bind returns a new function with the same body as the original function.

• The 'this' value of the new function is bound to the first argument passed to bind().

• The subsequent arguments are passed as arguments to the new function.

• Polyfill for bind() can be created using call() or apply() methods.

Create Linked List without using internal library and provide add, delete, find functionality.

• Create a Node class with data and next pointer

• Create a LinkedList class with head pointer and methods to add, delete, and find nodes

• Use a loop to traverse the list and perform operations

• Handle edge cases such as adding to an empty list or deleting the head node

Estimating the costs of an Auto-Rickshaw driver.

• Consider fuel expenses for the auto-rickshaw.

• Include maintenance and repair costs.

• Factor in license and permit fees.

• Account for insurance premiums.

• Include daily wages for any helpers or assistants.

• Consider miscellaneous expenses like parking fees and tolls.

I will explain each section of my CV in detail.

• Education: I completed my Bachelor's degree in Economics at XYZ University. I focused on macroeconomics and econometrics, conducting research on the impact of fiscal policy on economic growth.

• Internship: I interned at ABC Company, where I worked closely with the data analysis team. I gained hands-on experience in data collection, cleaning, and analysis using tools like Excel and SQL.

• Work Experience: I worked as a Junior Analyst a...read more

async loads script while page continues to load, defer loads script after page has loaded

• async loads scripts asynchronously while page continues to load

• defer loads scripts after the page has loaded

• async scripts may not execute in order, while defer scripts do

• async scripts may cause rendering issues, while defer scripts do not

I would listen to their concerns, empathize with their situation, and work with them to find a solution that meets their needs.

• Listen actively to understand their concerns

• Acknowledge their loyalty to the brand

• Empathize with their situation

• Collaborate with them to find a solution that meets their needs

• Provide options and alternatives if necessary

• Follow up to ensure their satisfaction

The amount of water used in the college depends on various factors such as the number of students, staff, and facilities.

• The amount of water used in the college varies depending on the size of the college.

• The number of students, staff, and facilities also play a significant role in determining the amount of water used.

• The college may have water-saving measures in place to reduce water usage.

• The amount of water used may also vary depending on the season and weather conditions....read more

Median is best because it is not affected by outliers and gives a better representation of central tendency.

• Median is the middle value in a dataset, which makes it less affected by extreme values or outliers.

• It gives a better representation of central tendency as compared to mean, which can be skewed by outliers.

• Mode is not always useful as it may not exist or may not be unique in a dataset.

• For example, in a dataset of salaries, the median would give a better representation o...read more

Calculate the level sum of a binary tree.

• Traverse the tree level by level using BFS

• Add the values of nodes at each level

• Store the level sum in an array

• Return the array of level sums

NoSQL databases are flexible, scalable, and can handle large amounts of unstructured data.

• NoSQL databases are schema-less, allowing for easy and flexible data modeling.

• They can handle large amounts of unstructured data, making them suitable for big data applications.

• NoSQL databases are highly scalable and can easily handle high traffic and large user bases.

• They provide horizontal scalability by distributing data across multiple servers.

• NoSQL databases are often used in real-t...read more

The number of rectangles in an MxN matrix can be calculated using a formula.

• The formula is (M * (M + 1) * N * (N + 1)) / 4

• The matrix can be divided into smaller sub-matrices to count the rectangles

• The number of rectangles can also be calculated by counting all possible pairs of rows and columns

Find the total no of islands in a 2D matrix.

• Use DFS or BFS to traverse the matrix.

• Mark visited cells to avoid repetition.

• Count the number of islands found.

I would apologize for the inconvenience and assure the customer that we will resolve the issue promptly.

• Apologize for the inconvenience caused

• Assure the customer that we will resolve the issue

• Ask for details about the damaged product

• Offer options for replacement, refund, or repair

• Provide clear instructions on returning the damaged product

A program to check if a number is a palindrome or not.

• Convert the number to a string

• Reverse the string

• Compare the reversed string with the original string

• If they are the same, the number is a palindrome

To find square root of a number, use Math.sqrt() function in JavaScript.

• Use Math.sqrt() function in JavaScript to find square root of a number.

• For example, Math.sqrt(16) will return 4.

• If the number is negative, Math.sqrt() will return NaN.

There are 204 squares and 1296 rectangles on a standard 8x8 chess board.

• The number of squares can be calculated using the formula n(n+1)(2n+1)/6, where n is the number of rows/columns.

• The number of rectangles can be calculated using the formula n(n+1)m(m+1)/4, where n and m are the number of rows and columns respectively.

• For an 8x8 chess board, there are 64 squares of size 1x1, 49 squares of size 2x2, 36 squares of size 3x3, 25 squares of size 4x4, 16 squares of size 5x5, 9 s...read more

The number of umbrellas sold in India during rainy seasons varies depending on factors such as rainfall intensity and geographical location.

• The demand for umbrellas is generally higher in regions with heavy rainfall.

• Urban areas with higher population density may have a higher demand for umbrellas.

• Factors like price, availability, and marketing strategies also influence umbrella sales.

• Sales data from previous years can provide insights into the average number of umbrellas sold...read more

Pre-order and post-order are traversal methods used in binary trees.

• Pre-order: visit root, left subtree, right subtree

• Post-order: visit left subtree, right subtree, root

• Used to traverse binary trees and perform operations on nodes

• Example: Pre-order traversal of binary tree: A, B, D, E, C, F, G

• Example: Post-order traversal of binary tree: D, E, B, F, G, C, A

Estimating the revenue of a Dominos outlet

• Consider the average number of orders per day

• Calculate the average order value

• Multiply the average number of orders by the average order value

• Take into account any seasonal variations or promotions

• Consider the location and population density of the outlet

• Analyze the competition in the area

• Factor in the operating expenses and profit margin

Reverse a linked list iteratively

• Create three pointers: prev, curr, and next

• Initialize prev to null and curr to head

• Loop through the list and set next to curr's next node

• Set curr's next node to prev

• Move prev and curr one step forward

• Return prev as the new head

No, 899 is not a prime number.

• A prime number is a positive integer greater than 1 that has no positive integer divisors other than 1 and itself.

• 899 can be divided by 29 and 31, so it is not a prime number.

By analyzing data, identifying pain points, and implementing solutions to improve user experience and trust.

• Analyze user behavior and feedback to identify areas of improvement

• Implement measures to increase transparency and trust, such as user reviews and seller verification

• Provide resources and support for dispute resolution

• Encourage diversity and inclusivity in the marketplace to attract a wider range of buyers and sellers

• Regularly monitor and update policies to ensure compl...read more

I will design a customer support system that is user-friendly, efficient, and personalized.

• Conduct research to understand customer needs and preferences

• Identify common customer issues and develop a knowledge base for quick resolution

• Implement a ticketing system to track and prioritize customer inquiries

• Integrate chatbots and AI to provide 24/7 support

• Train support staff to provide personalized and empathetic service

• Collect feedback and analyze data to continuously improve the...read more

Tree traversals are methods of visiting all nodes in a tree data structure.

• There are three types of tree traversals: in-order, pre-order, and post-order.

• In-order traversal visits the left subtree, then the root, then the right subtree.

• Pre-order traversal visits the root, then the left subtree, then the right subtree.

• Post-order traversal visits the left subtree, then the right subtree, then the root.

• Tree traversals are commonly used in searching and sorting algorithms.

To excel in my role and contribute to the growth of the company.

• To learn and master new skills

• To exceed performance expectations

• To collaborate with team members and share knowledge

• To contribute to the company's success through hard work and dedication

The current system follows a microservices architecture.

• The system is divided into multiple independent services.

• Each service has its own database and communicates with other services through APIs.

• The architecture allows for scalability and flexibility.

• Examples of microservices used in the system include user authentication, payment processing, and inventory management.

The answer describes how to check if a linked list is a palindrome or not.

• Traverse the linked list and store the values in an array

• Compare the elements of the array from both ends to check for palindrome

• Alternatively, use two pointers to traverse the linked list, one slow and one fast, and reverse the first half of the list while traversing

To find the Kth element from the end of a linked list, we can use the two-pointer approach.

• Initialize two pointers, 'fast' and 'slow', pointing to the head of the linked list.

• Move the 'fast' pointer K steps ahead.

• Move both 'fast' and 'slow' pointers one step at a time until 'fast' reaches the end of the linked list.

• The 'slow' pointer will be pointing to the Kth element from the end.