151. 翻转字符串里的单词

class Solution 
{
    //spilt函数的实现
    //假设以空格切分:char c = ' ';
    vector<string> res; 
    void spilt(string s,char c,vector<string> &res)
    {
        istringstream iss(s);
        string temp;
        while(getline(iss,temp,c))
        {
            //如果temp不为空，才可以添加进去
            if(!temp.empty()) res.push_back(temp);
        }
    }
public:
    string reverseWords(string s) 
    {
        string str;
        spilt(s,' ',res);
        if(res.empty()) return "";
        for(auto a : res) str = a + " " + str;
        str.pop_back();
        return str;
    }
};