Reverse Words in a String

Given an input string, reverse the string word by word.

For example,
Given s = "the sky is blue",
return "blue is sky the".

Clarification:

• What constitutes a word?
  A sequence of non-space characters constitutes a word.
• Could the input string contain leading or trailing spaces?
  Yes. However, your reversed string should not contain leading or trailing spaces.
• How about multiple spaces between two words?
  Reduce them to a single space in the reversed string.

这个题目好像在研究生某一年一道机试题目，以前用C++处理起来比较麻烦，利用java中String 提供的方法非常简单就能解决问题。

public class Solution {    public String reverseWords(String s) {        String [] numStrings = s.split(" ");        String result = "" ;        for(int i=numStrings.length-1;i>=0;i--){        if(!(numStrings[i].equals("")))        result += numStrings[i]+" ";        }        result = result.trim();        return result;    }}

通过“ ”进行分割，如果有多个空格，分割出来的为空，进行判断就行，最后trim方法把多余空格消除。