Abbreviation

Write a function abbreviation(sentence) that takes a string of words separated by spaces and returns its abbreviation: the first letter of each word in uppercase, joined by dots, with a trailing dot at the end. Use a comprehension rather than an explicit loop.

Example

abbreviation('central processing unit')  ->  'C.P.U.'

Your task

Implement this function:

def abbreviation(sentence: str) -> str:

Write the function only — the arguments are read for you and the return value is printed automatically.

Arguments arrive as one Python literal per line, in this order: sentence.

Example

Input

'central processing unit'

Output

'C.P.U.'