task

import java.util.Scanner;
import java.util.HashSet;
public class Main
{
    public static void main(String[] args) {

        Scanner in = new Scanner(System.in);
        int N;
        N = Integer.parseInt(in.nextLine());
        HashSet<String> mails = new HashSet<String>();
        for(int i = 0; i < N; i++) {
            String mail = "", login="", domen="";
            mail = in.nextLine();
            while (mail == "")
                mail = in.nextLine();
            int indexOfDog = mail.indexOf("@"), indexOfDefis = mail.indexOf("-");
            login = mail.substring(0, indexOfDog);
            if (indexOfDefis!=-1)
                login = login.substring(0, indexOfDefis);
            login = login.replace(".", "");

            domen = mail.substring(indexOfDog+1, mail.length());
            int dotIndex = domen.lastIndexOf(".");
            if (dotIndex!=-1)
                domen = domen.substring(0, dotIndex);

            mail = login + "@" + domen;
            mails.add(mail);
        }
        System.out.println(mails.size());
        in.close();
    }
}