import java.util.HashMap;
import java.util.Map;
class logonSystem
{
    public static void main(String args[])
    {
        System.out.print("\n\n\n\n\n\n\n\n\n\n\n");
        Map usermap = new HashMap();
        while(true)
        {
            String username, password;
            System.out.print("Enter a username (enter nothing to stop adding users) : ");
            username = Keyboard.readString().toLowerCase();
            if (username.compareTo("") == 0)
                break;
            System.out.print("Enter a password : ");
            password = Keyboard.readString();
            usermap.put(username, password);
        }
        System.out.print("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n");
        System.out.print("Enter your login name : ");

        String username = Keyboard.readString().toLowerCase();
        if (!usermap.containsKey(username))
        {
            System.out.println("No such username.");
            return;
        }

        System.out.print("Enter your password : ");
        String password = Keyboard.readString();
        if (((String)usermap.get(username)).compareTo(password) == 0)
            System.out.println(username + ", you have logged in successfully.");
        else
            System.out.println("Bad password provided.");
    }
}