Create Reverse Words in a String

按照空格切分String[] strs = s.split(" ");
减去尾部的空格s = s.trim();很关键。比如输入" A          B" 输出时候为“B A”而不是“B            A”

Given an input string, reverse the string word by word.

For example,
Given s = "the sky is blue",
return "blue is sky the".