I'm shocked that over twice as many users solved this with the ternary than without.

This does not preseve whitespace.
" this is wrong" should arguably still include a leading space (as said by babakgh)
"this [space space space] is wrong" should arguably still have multiple spaces between 'this' and 'is'
EDIT: Aparently codewars also doesnt preserve multiple whitespace even in code blocks, but hopefully its clear what I mean

\d is short for [0-9]

https://www.regular-expressions.info/shorthand.html

Fails with this " this is wrong "

I have no idea with recursion solution :) But your & my code working fine with big n :)

You are absolutely right, sir.
First time ever I see that recursion is actually not a clever thing to do.

Is it still somehow possible to run this code with n = 100? Mine returns "Interupt" error.

That is Bad Practice! What about if n == 100? :) Your program will kill itself.

test this:

I say "go"

It won't work

it's a very neat and idiomatic code but as the pattern you capitalize is defined in split, it is not robust nor flexible at all.

Then you displays a validation error until the user types without any errors.

what if space symbol is missed by a mistake, like: "No body really cares,what are you thinking about."

Thanks!
I also found this useful for anyone newer

https://www.youtube.com/watch?v=zg-ddPbzcKM

This is an example of recursion. The concept is present in many programming languages, and mathematics in general.

The equation for a single fibonacci number is dependent on the two previous fibonacci numbers (for all but n == 1 && n == 2). These are determined by either:

• Calling the fibonacci method again from within the fibonacci method itself (which may in turn call itself many more times, until it hits a seed value).
• Hitting an n value that acts as a seed. These seed values are required to prevent infinite recursion, and are implemented as the following lines in this solution:

return 0 if n == 1
return 1 if n == 2

For a ruby specific explanation of recursion, check out this StackOverflow Post.

For a more broad, mathematical explanation (including fibonacci numbers) see the wiki article on Recurrence relations.

Can someone explain how this works?
Newer to ruby and don't understand this method with a method call...?

nth_fibonacci(n-1)+nth_fibonacci(n-2)