LeetCode: Reverse Words in a String

 1 class Solution {
 2 public:
 3     void reverseWords(string &s) {
 4         vector<string> words = split(s);
 5         s.clear();
 6         vector<string>::reverse_iterator iter = words.rbegin();
 7         if(iter != words.rend()){
 8             s += *iter;
 9             ++iter;
10         }
11         for(; iter != words.rend(); ++iter){
12             s += " ";
13             s += *iter;
14         }
15     }
16     vector<string> split(const string &s){
17         string t;
18         vector<string> words;
19         string::const_iterator p = s.begin();
20         while(p != s.end()){
21             while(p != s.end() && isspace(*p)){
22                 ++p;
23             }
24             while(p != s.end() && !isspace(*p)){
25                 t.push_back(*p);
26                 ++p;
27             }
28             if(!t.empty()){
29                 words.push_back(t);
30                 t.clear();
31             }
32         }
33         return words;
34     }
35 };