Solution so I can move on please!

JavaScript
1

Hi, I have been struggling with this problem for 2 days now, and I just want to see the solution so I can learn what I am missing. The recursion is very hard for me to understand.

Your code so far


function sum(arr, n) {
// Only change code below this line
if (n<=1) {
return 0;
} else {
sum[n - 1];
}
// Only change code above this line
}

Your browser information:

User Agent is: Mozilla/5.0 (X11; CrOS x86_64 13310.76.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/85.0.4183.108 Safari/537.36.

Challenge: Replace Loops using Recursion

Link to the challenge:

1 Like
2

Welcome to the community!

Sorry to hear that you’ve been struggling with this. If you click on “Get Help” then “Get a Hint”, you’ll be taken to a post with hints + possible solutions. You can find a solution there to help guide and direct you for this particular challenge.

For your ease, this is the page: freeCodeCamp Challenge Guide: Replace Loops using Recursion

1 Like
3

Ah, yes. I’ve seen this solution, but thanks for the reference! The problem with the given solution is giving me an error for these things `

sum([1], 0)` should equal 0.

sum([2, 3, 4], 1) should equal 2.

sum([2, 3, 4, 5], 3) should equal 9.

I’m not sure what I’m supposed to do or what to add to the problem in order to move forward.

4 Likes
4

Hello and welcome to the freeCodeCamp community~!

I ran the solution from the guide post @darren-stoll linked for you against the tests in the challenge, and everything passes on my end. The solution appears to be correct. Can you share your current code again?

5

Hi, thank you all for the welcome! I deleted the comment codes and it worked. Thank you again.

1 Like
6

I am glad you were able to solve it! I do, however, strongly encourage that you spend the time to understand recursion. It’s a powerful tool to have in your kit. :slight_smile:

3 Likes
7

if you reall just want to move one, just go to the lists of challenges and select the next challenge - challenges are not mandatory for the cert

your issue is that you have the call sum[n-1] which is not the correct way to call a function plus you are not doing anything with it

1 Like
8

Hey @rylidavis94!

First off, I am glad that you were able to figure out the solution. I do agree with @nhcarrigan’s advice about spending extra time on this topic because it will come up again later on in the javascript section.

This is a helpful video explaining how recursion works and what is actually happening inside the computer.

I would also highly suggest that you watch Colt’s other video on call stacks as well

Hope that helps!

Happy coding!

21 Likes
9

That first video really REALLY helped me understand what was happening! Thank you so much. I did not realize that all of these returns were pending until the base case was hit. I made this account just to express my gratitude. I passed the challenge just fine but did not really grok what was going on.

5 Likes