thank you!!

I am also a noob. But I think the slice.eq(something_else) is using a trait functionality. And the Eq trait is listed in the trait section (below the methods) in the link you provided.

Here is the link to that spot on the page:
https://doc.rust-lang.org/std/primitive.slice.html#impl-Eq

Need my brain charged xD

Simple and straightforward. But time consuming.

Sum is slow.
For large numbers one should use (start + end) * 2 / diff.

OMG
Fancy
Sexy
Clever
Marry me!

Now that's brute force xD

With my respect...