Zepto Senior Data Scientist Interview Questions and Answers

I was asked question on sliding window on finding the largest subarray with all distinct numbers. The interviewer was very helpful.

Q1. What is event loop, how it works.
Ans. 
Event loop is a mechanism in programming that allows for asynchronous execution of code by continuously checking for and handling events.
• Event loop is commonly used in JavaScript to handle asynchronous operations like setTimeout, setInterval, and AJAX requests.

• It works by continuously checking the event queue for any pending events, executing them one by one, and then moving on to the next event.

• Event loop helps in pre...read more
Answered by AI
Add your answer
Q2. Micro task queue and macro task queue.
Add your answer
Q3. Is node.js single threaded or multi-threaded, also discuss threadpool and it's usages.
Add your answer
Q4. Tell the order of output, among process, promise, setTimeout, fs, setInterval.
Ans. 
The order of output is fs, process, setTimeout, setInterval, promise.
• fs module is synchronous and will output first

• process is next in line

• setTimeout will be executed after process

• setInterval will be executed after setTimeout

• promise will be executed last
Answered by AI
Add your answer

Q1. JavaScript usages compiler or interpreter.
Ans. 
JavaScript is an interpreted language.
• JavaScript is an interpreted language, meaning it is executed line by line at runtime.

• There is no separate compilation step in JavaScript like in languages that use compilers.

• Examples of interpreted languages include Python, Ruby, and PHP.
Answered by AI
Add your answer
Q2. Tell the output among various for loops using var, let and bind.
Ans. 
Output comparison of for loops using var, let, and bind in JavaScript.
• Using var: variable is function-scoped, may lead to unexpected behavior in loops.

• Using let: variable is block-scoped, recommended for loop iterations.

• Using bind: creates a new function with a specified 'this' value and initial arguments.
Answered by AI
Add your answer
Q3. A medium level dsa question on array, solved it using pre-sum.
Add your answer
Q4. Situation based question, on how to pick a suitable database.
Add your answer

Q1. What do you do on daily basis, and how to decide a tech-stack on high level.
Ans. 
I work on coding, debugging, testing, and collaborating with team members. Tech stack decisions are based on project requirements, scalability, performance, and team expertise.
• Daily tasks include coding, debugging, testing, and collaborating with team members

• Tech stack decisions are based on project requirements, scalability, performance, and team expertise

• Consider factors like language compatibility, libraries/framewo...read more
Answered by AI
Add your answer
Q2. Design an online scalable, real-time document sharing application like google docs.
Ans. 
Design a scalable, real-time document sharing app like Google Docs.
• Use websockets for real-time collaboration

• Implement version control to track changes

• Utilize a distributed database for scalability

• Include user authentication and access control

• Support offline editing with automatic sync
Answered by AI
Add your answer
Q3. How to handle images also in the future.
Ans. 
Utilize cloud storage for scalability, implement image compression techniques, and regularly update image processing libraries.
• Utilize cloud storage for scalability

• Implement image compression techniques

• Regularly update image processing libraries
Answered by AI
Add your answer
Q4. Any other way to solve the problem, of high I/O on same document to overcome throughput and conflicts.
Add your answer

Q1. Create a controller , service and repository methods and classes to save userDeatils in table using Spring Data JPA .
Ans. 
Create a controller, service, and repository to save user details using Spring Data JPA.
• Create a UserController class with appropriate mappings for saving user details.

• Create a UserService class with a method to save user details.

• Create a UserRepository interface that extends JpaRepository to handle database operations.

• Implement the saveUserDetails method in the UserService class to call the save method of the UserRepo...read more
Answered by AI
Add your answer

Q1. Template and Reactive Forms in Angular
Ans. 
Template and Reactive Forms in Angular are two ways to handle forms in Angular applications.
• Template Forms are based on the traditional HTML forms and are easy to use for simple forms.

• Reactive Forms are more flexible and powerful, allowing for complex form validation and dynamic form controls.

• Template Forms use two-way data binding, while Reactive Forms use a more reactive approach with observables.

• Reactive Forms are r...read more
Answered by AI
Add your answer

Q1. Fundamentals and Basics of android, projects you are worked on.
Add your answer

It was sort of pair programming where you will be told to implement some feature. Here they check your coding style, your approach and the architecture you follow.

Q1. Advanced android questions were asked and some scenario based questions.
Add your answer

Q1. It was managerial round, most discussion were on my projects and past experience.
Add your answer

Q1. Job experience, introduction
Add your answer

Q1. Working experienced
Add your answer

Final assignment to complete