Note that this has time complexity O(N^2) while it's possible to achieve O(N).

Never mind, the piece of optimisation I failed to figure out was checking for a set rather than the entire string. My bad.

I continuously timed out with this exact solution...

I'm new to programming and if I'm wrong please someone correct me!

I believe it's because it's being considered to be null terminated strings.
Therefore the last character of these strings are '\0', but in a empty string this would be the only character
and when we compare it with a string that isn't empty it would return true since '\0' is present in both.

But as far as I understand it isn't something that will be printed in the screen, just something that will be
considered by the machine.

How could this pass the test while my first try failed?
This should report an error with empty input of s2,
when you try scramble('r',''), this code return True while it should be False.