Leetcode-151. Reverse Words in a String

前言：为了后续的实习面试，开始疯狂刷题，非常欢迎志同道合的朋友一起交流。因为时间比较紧张，目前的规划是先过一遍，写出能想到的最优算法，第二遍再考虑最优或者较优的方法。如有错误欢迎指正。博主首发CSDN，mcf171专栏。

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

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

Update (2015-02-12):
For C programmers: Try to solve it in-place in O(1) space.

click to show clarification.

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.

这个题目也挺简单的，就是有一个地方要注意，通过" "空格去分割的时候会出现""的情况，需要排除一下。Your runtime beats 90.66% of java submissions.

public class Solution {    public String reverseWords(String s) {        String[] splits = s.split(" ");        StringBuffer sb = new StringBuffer("");        if(splits.length > 0 && !splits[splits.length - 1].equals(" ") && !splits[splits.length - 1].equals("") ) sb.append(splits[splits.length -1]);        for(int i = splits.length - 2; i >= 0; i--){            if(!splits[i].equals(" ") && !splits[i].equals("")){sb.append(" ");sb.append(splits[i]);}        }        return sb.toString();    }}