SDE - Intern

You are given a non-decreasing array 'arr' consisting of 'n' integers and an integer 'x'. You need to find the first and last position of 'x' in the array.

Note:

1. The array follows 0-based indexing, so you need to return 0-based indices.
2. If 'x' is not present in the array, return {-1 -1}.
3. If 'x' is only present once in the array, the first and last position of its occurrence will be the same.

Example:

Input:  arr = [1, 2, 4, 4, 5],  x = 4

Output: 2 3

Explanation: The given array’s 0-based indexing is as follows:
 1      2     4     4     5
 ↓      ↓     ↓     ↓     ↓
 0      1     2     3     4

So, the first occurrence of 4 is at index 2, and the last occurrence of 4 is at index 3.

You are given a binary tree with 'N' nodes. Each node has an integer value associated with it. You are also given an integer 'Target'. Your task is to determine the total number of different paths such that the sum of values of nodes in each path equals 'Target'.

Note :

A path may or may not start at the root of the tree. A path may or may not end on a leaf node. You are allowed to travel only downwards. This means after visiting any node, you are allowed to visit only its children.

You have been given ‘N’ courses and some courses may have prerequisites. Now consider a matrix ‘PREREQUISITES’ of size 'M' x 2 which represents that you must complete the course 'PREREQUISITES[i][1]' before the course 'PREREQUISITES[i][0]'.

Your task is to return the order of courses you should take to finish all courses.

Note:

If it is impossible to finish all courses, return an empty array. If there are multiple answers, return any one.

For example:

Input:
3 2
1 2
2 3

There are three courses to take. To start with, First course 3 is taken. Then course 2 is taken for which course 3 must be completed. 

At last course 1 is taken for which course 2 must be completed. So the correct course order is [3,2,1].    

Develop a real-time chat application with camera and microphone integration, leveraging
OpenAI's API, Socket.io, and MongoDB. The app will feature text-to-speech and speech-to-text
capabilities.

Initialize a new MERN (MongoDB, Express.js, React.js, Node.js) project.
Install required npm packages: Express, Socket.io, Mongodb, Openai, and additional libraries
for text-to-speech and speech-to-text services.
Set up a Figma-based UI design for the application, including camera and microphone controls.

Backend Development:
Set up an Express server.
Configure Socket.io for real-time communication.
Integrate MongoDB for chat history storage.
Create endpoints for OpenAI API communication.
Implement text-to-speech and speech-to-text services.

Frontend Development:
Develop a React-based frontend according to the Figma design.
Implement camera and microphone functionality with enable/disable options.
Ensure real-time chat display and interaction.
Integrate Socket.io client for seamless server communication.

Can you explain how Socket.io facilitates real-time communication in your chat application? What are some key features it provides for managing connections and broadcasting messages?

How did you integrate OpenAI's API into your application? Can you describe a specific use case where the AI features (like text-to-speech or speech-to-text) enhance the user experience?

What considerations did you take into account when designing the MongoDB schema for storing chat history? How did you ensure efficient retrieval and storage of messages?

How did you implement camera and microphone functionality in the chat application? What challenges did you face regarding user permissions and how did you address them?