Description is inadequate. How many functions do we need to support for map, filter and subscribe? How many arguments do we need to support for notify?

You use my kata https://www.codewars.com/kata/adding-values-of-arrays-in-a-shifted-way for a new kata?
I do not know what to think about that.

I am between two options:

1. Delete your kata! It is a cheap copy of my kata!
2. You should add a reference to the original kata!

Next time create an own kata basing on a new idea from you!