Loading collection data...
Collections are a way for you to organize kata so that you can create your own training routines. Every collection you create is public and automatically sharable with other warriors. After you have added a few kata to a collection you and others can train on the kata contained within the collection.
Get started now by creating a new collection.
The ones that invoke the map method?
That's pretty sweet :)
valid point. I don't know what I was thinking.
I feel pretty stupid when I see how short all the other solutions are T.T
It seems like some random cases have multiple solutions, in which case it expects what seems like the last sum you found if you work from left to right (might have been a coincidence, but that's what passed the random tests in my case). Any of the sums should be correct though.
Only a small issue:
My solution only kept letters, and removed both special characters AND numbers (despite the description stating numbers matters).
However, it still passed all the tests. I don't think this is intentional.