290. 单词规律

class Solution 
{
    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:
    bool wordPattern(string pattern, string str) 
    {
        spilt(str,' ',res);
        unordered_set<string> u;
        if(pattern.size() != res.size()) return false;
        unordered_map<char,string> hash;
        for(int i = 0;i < pattern.size();i ++)
        {
            if(hash.count(pattern[i]) && hash[pattern[i]] != res[i]) return false;
            if(hash.count(pattern[i]) == 0 && u.find(res[i]) != u.end()) return false;
            hash[pattern[i]] = res[i];
            u.insert(res[i]);
        }
        return true;
    }
};