NodeJS Code Challenges & Tips

1. Write a function that takes an array of numbers and returns a new array with all the duplicate numbers removed.

2. Implement a simple in-memory key-value store (like Redis) with set, get, and delete methods in Node.js.

3. Write a function that reverses a string without using the built-in reverse methods.

4. Create a middleware function in an Express app that logs the request method and URL for each incoming request.

5. Write a function that merges two sorted arrays into one sorted array.

6. Implement a basic Rate Limiter for an API endpoint using middleware in Node.js.

7. Create a function to flatten a nested array of arbitrary depth into a single array.

8. Write a function that takes a sentence and returns the words sorted by their length in ascending order.

9. Implement a Promise-based function that resolves after a given number of milliseconds and rejects if the number is negative.

10. Write a Node.js script that reads a JSON file and outputs the total number of entries in the JSON object.