Finding the right code and make it work out on your own is a lot more rewarding from my perspective and I think not only mine, in this kata and many other ones you get to practice some dynamic programming concepts basically, optimization, algorithm efficiency, which is something that's already there and every coder should at least try to get familiar with, you've only got to do better and more research sometimes to get a deeper general idea.

I think Switch would be better practice.

Is it worth it?

always. But the time needed/difficulty could vary A LOT, depending on what's your current knowledge about algorithms. For this problem, if you're a very beginner, you should leave it for later, maybe.

Do you guys create the solution completely on your own? I know it is possible to implement some algorithm from google but I wonder how hard it could be to invent the solution completely on your own. Is it worth it?