class Solution {
public:
    string reverseWords(string s) {

        if(s=="") return s;
        s+= ' ';
        stack<string> cache;
        string output = "";
        string temp = "";

        for(int i =0 ; i < s.length(); i++){
            if(s[i] == ' '){
                if(temp != ""){cache.push(temp);}
                temp = "";
            }
            else{
                temp += s[i];
            }
        }

        while(! cache.empty()){
            output += cache.top();
            output += ' ';
            cache.pop();
            }

        if (output =="") return output;
        output.pop_back();
        return output;
    }
};