Reverse Words in a String flip the word order in a String @ LeetCode

Reverse Words in a String flip the word order in a String @ LeetCode

LeetCode is a new question, but it is relatively simple. Use the stack directly.

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

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

Click to show clarification.

Clarification:

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

  public class Solution {    public String reverseWords(String s) {        if(s.length() == 0) {            return s;        }        Stack
     
       stack = new Stack
      
       ();        String[] ss = s.split("\\s+");        for(String word : ss) {            stack.push(word);        }        StringBuilder sb = new StringBuilder();        while(!stack.isEmpty()) {            sb.append(stack.pop()).append(" ");        }        return sb.toString().trim();    }}