codeforces 118A - String Task

vowels=['a','e','i','o','u','y']
def sol(s):
    ans=''
    s=s.lower()
    for i in vowels:
        s=s.replace(i,'')
    for i in s:
        ans+='.'
        ans+=i
 
    return ans
s=input()
print(sol(s))