import string
EMAIL_CHARS = string.ascii_letters + string.digits + '.'

def find_name_start(text, at_index):
    first_index = 0
    for index in range(at_index-1, -1, -1):
        if text[index] == at_index:
            break

        if text[index] not in EMAIL_CHARS:
            first_index = index + 1
            break
    return first_index

def find_name_end(text, at_index):
    first_index = 0
    for index in range(at_index+1,len(text)):

        #if text[index] == at_index:
           # break
        if text[index] not in EMAIL_CHARS:
            first_index = index + 1
            break
        if index == len(text)-1:
            first_index = index + 1
            break
    # if text[index] == 0:

    return first_index

def find_email(text):
    at_index = text.find('@')


    email_list = []
    while at_index > -1 :
        name_start = find_name_start(text, at_index)
        name_end = find_name_end(text, at_index)

        email = text[name_start : name_end]
        email_list.append(email)

        if name_start == at_index:
            email_list.remove(email)
            #if email_list == []:
              # print "Please, type in an email address"
              # return

        if name_end - 2 == at_index and name_end == 0:
            email_list.remove(email)

       # if name_end == 0:
            #email_list.remove(email)


        at_index = text.find('@',at_index+1)


    return email_list



#print find_email("@gmail.com olle@gmail.com")
#print find_email("olle@gmail.com @gmail.com")
#print find_email("olle@ olle@gmail.com")
#print find_email("olle@gmail.com olle@")
#print find_email("@olle olle@gmail.com @olle")
#print find_email("@gmail.com olle@gmail.com @gmail.com")
#print find_email("")
#print find_email("hej ehj olle@gmail.com @sfeeahfaf 1234 {[]9)8?#&")
print find_email("@ olle@gmail.com")