How to solve this challenge?

1. Read the "Challenge description" below.
2. Make changes to the challenge.js file.
3. Commit your changes.
4. Wait for the result of the "GitHub Classroom Workflow" action. If it is green - congratulations, you solved this challenge! If not - try again!
5. You can watch an example of how to solve a challenge in this video

Challenge description

Basic Recursion

You will be given a positive integer number . Fill in the method sum so that it adds up all the positive integers up to number and returns the sum. For example, when given 4 it should return 10 (4+3+2+1).

While there are other ways to solve this challenge, you should use recursion to get the sum.

Examples

console.log(sum(4))
// => (4 + 3 + 2 + 1) = 10

console.log(sum(10))
// => 55

Get stuck and need some hint? Check this link: https://gitlab.com/microverse/guides/coding_challenges/hints/blob/master/challenges/recursion/basic-recursion.md