Reverse Words in a String II

Given an input string, reverse the string word by word. A word is defined as a sequence of non-space characters.

The input string does not contain leading or trailing spaces and the words are always separated by a single space.

For example,

Given s = "the sky is blue",

return "blue is sky the".

Could you do it in-place without allocating extra space?

class Solution(object):
    def reverseWords(self, s):
        """
        :type s: a list of 1 length strings (List[str])
        :rtype: nothing
        """

        s[:] = list(' '.join(reversed(''.join(s).split(' '))))