【Leetcode_easy】929. Unique Email Addresses

class Solution {
public:
    int numUniqueEmails(vector<string>& emails) {
        unordered_set<string> tmp;
        for(auto email:emails)
        {
            std::size_t at = email.find('@');
            string local = "";
            for(int i=0; i<at; i++)
            {
                if(email[i]=='.') ;
                else if(email[i]=='+') break;
                else local += email[i];
            }
            tmp.insert(local+'@'+email.substr(at+1));//errr...
        }
        return tmp.size();
    }
};