I think int(l**.5) is explicit enough, floor confuses more then it helps imo

True, but it's more explicit that way.

fixed

• Your gsub! modified the input. If you want to make a copy of input string, please use s = x + ""

• The result of your solution is wrong. It can not handle the testcase like this: Test.assert_equals(zero_and_one("110100"),2).

• This is what happened when I used x and y as my variables. It's not the truth. I guess that you want to do some test but not changed all the name s to x(or y).

Please try again O_o

Fixed.

Ok, try it now.

Ha, that was something stupid on my part, fixing it now.

.

Try it now.

Looks to be fixed in Ruby.

Fixed.

Fixed (I hope).