using System;

using System.Linq;

public class Program

{

    public static void Main()

    {

        string email = Console.ReadLine();

        int count = email.Count (f => f == '@');

        if (count == 1)

{

        Console.WriteLine("Emaila baliogarria da");

        }

        else 

{

        Console.WriteLine("Emaila ez du balio");

        }

    }

}

​

​

​