because he used 'i' and the first used 'x'

Bro, I tried the same thing but they showed me error! donno why!

Why isn't this grouped with the first solution?

Bad

use'while', not'if'

Hey! nadolski's explenation is much better than I could give at the moment as I'm new to regex and this one is partially taken from stack overflow and partialy changed by me!

Good solution, but it must be like this: /.+//|www\.|..+/g ("\" after "www"). Because the URL "http://www4cnet.com" will reutrn 'cnet' instead of 'www4cnet'.

The moment i saw the question i understood i had to use regex but i am not good at it, probably scared of the syntax. But this looks good and i will definitely check the solution.

The tests are fine. Please post your code with spoilers and raise this kind of problems as a question next time :)

Please, explain the regex. The last part of it (|..+ ) looks like the queried value. How can it be, that it doesn't replaced with "", like everything before it?
Thanks!

[1].pop() will return 1, not undefined.