why would that be inefficient? starting with python now and I used sorted() as well.
what do you mean by "O(n log n)"?

you can view their solution by clicking on 'View Solution'

can you solve it by o(n) please?

No you cant do that, it would contain 0 and we dont want that

you can use '_' instead, it just a placeholder

This assessment is correct. The tests are incomplete and do not cover all of the necessary cases to determine whether the spec has been met.

its just because without it, the functions assumes W is the index and the last parameter is left off. The functions isnt aware of the parameter name, just the location of the parameter within the callback.

The question you're asking is, "What if this kata was a different kata?"

Then I would have written different code. But it's not a different kata. It's this kata. And in this kata the arrays always have an equal number of elements.