648. 单词替换

648. 单词替换

class Solution {
public:
    string replaceWords(vector<string>& dictionary, string sentence) {
        sort(dictionary.begin(), dictionary.end());
        vector<string> word;
        string temp;
        for (auto x : sentence)
        {
            if (x != ' ')
                temp.push_back(x);
            else
            {
                word.push_back(temp);
                temp.clear();
            }
        }
        word.push_back(temp);
        // cout << word.size() << endl;
        // for (auto x : word) cout << x << endl;
        string ret;
        for (auto x : word)
        {
            bool is_root = false;
            for (auto y : dictionary)
            {
                if (x.find(y) == 0)
                {
                    is_root = true;
                    ret += y;
                    break;
                }
            }
            if (!is_root)
                ret += x;    
            ret += " ";
        }
        ret.erase(ret.end() - 1);
        return ret;
    }
};