return re.fullmatch(r'[a-z0-9_-]+@[a-z0-9]+\.[a-z]{1,3}',s,re.I)

def fun(s):
    
    delimitor= ['@', '.']
    for i in delimitor:
        s= s.replace(i, " ")
    s= s.split(" ")
   
    if len(s) == 3 and all([i != '' for i in s]):
        if (all(c.isalnum() or c in ('-', '_') for c in s[0])
        and s[1].isalnum() and s[2].isalpha() and len(s[2]) <= 3):
            return True
        else:
            return False
    
def filter_mail(emails):
    return list(filter(fun, emails))

if __name__ == '__main__':
    n = int(input())
    emails = []
    for _ in range(n):
        emails.append(input())

filtered_emails = filter_mail(emails)
filtered_emails.sort()
print(filtered_emails)

def fun(s):
    
    delimitor= ['@', '.']
    for i in delimitor:
        s= s.replace(i, " ")
    s= s.split(" ")
   
    if len(s) == 3 and all([i != '' for i in s]):
        if (all(c.isalnum() or c in ('-', '_') for c in s[0])
        and s[1].isalnum() and s[2].isalpha() and len(s[2]) <= 3):
            return True
        else:
            return False
    
def filter_mail(emails):
    return list(filter(fun, emails))

if __name__ == '__main__':
    n = int(input())
    emails = []
    for _ in range(n):
        emails.append(input())

filtered_emails = filter_mail(emails)
filtered_emails.sort()
print(filtered_emails)

def fun(s):
    # return True if s is a valid email, else return False
    if(s.count("@") != 1 or s.count(".") != 1):
        return False
        
    name, web, ext = s.replace(".", "@").split("@")

    name = name.replace("_", "").replace("-", "")
    if(not name.isalnum() or not web.isalnum()):
        return False
    
    if(not ext.isalpha() or len(ext) <= 0 or len(ext) > 3):
        return False
    
    return True

import re

def fun(s):
    # return True if s is a valid email, else return False
    # username@websitename.extension
    
    pattern = r'^[\w-]+@[a-zA-Z0-9]+\.[a-zA-Z]{1,3}$'
    
    return re.match(pattern, s)