import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
String str = scanner.next();
int count1 = str.indexOf("@");
int count2 = str.indexOf(".com");
if(count1!=-1&&count2!=-1&&count1<count2&&count1!=0)
{
System.out.println("邮箱格式合法");
}
else{
System.out.println("邮箱格式不合法");
}
}
}