Reverse Words in a String (variant)

Given a string s containing words and spaces, return the string with the order of words reversed. Requirements: Words are separated by one or more spaces. In the output, words must be separated by a single space. The result must not contain leading or trailing spaces. Follow-up: If the input is provided as a mutable character array / mutable string, can you do it with O(1) extra space (in-place approach)? Examples Input: " the sky is blue " Output: "blue is sky the" Constraints 1 <= len(s) <= 1e5 s contains visible characters and spaces (at least one word) Example Input the sky is blue Output blue is sky the