leetcoder系列001：c++字符串反转

问题：

给定一个输入字符串，字符串字反向词。例如

 s = "the sky is blue",
返回 "blue is sky the".

我的答案：

class Solution {
public:
    void reverseWords(string &s) {
        if(s.size() <= 0)
            return;
            
        string pattern = " ";
        string::size_type pos;
        vector<string> result;
        s += pattern;
        string::size_type size = s.size();
        for(int i = 0;i < size;i++){
            pos = s.find(pattern, i);
            if(pos < size){
                string word = s.substr(i, pos - i);
                if(word.find(pattern) == -1 && word != "")
                    result.push_back(word);
                i = pos + pattern.size() - 1;
            }
        }
        
        s = "";
        if(result.size() <= 0)
            return;
        for(int i = result.size() - 1; i >= 1 ; i--){
          s += result[i];
          s += " ";
        }
        s += result[0];
    }
};