Some computer science courses at the University of Fireloo teach a programming language called Bracket.
Two of the functions in Bracket are (car x)
and (cdr x)
. These functions are used a lot, so the Bracket developers allowed programmers to "combine" multiple uses of (car x)
and (cdr x)
into one name.
Suppose that the function is (cijk...r x)
, where i
,j
,k
,... are characters each representing either a
or d
. This function is equivalent to (cir (cjk...r x))
, which is equivalent to (cir (cjr (ck...r x)))
, and so on. Note that the placement of the brackets is important. A full expansion only contains car
and cdr
functions.
For example, (cadadr x)
can be fully expanded to become (car (cdr (car (cdr x))))
.
Given a function in the form (cijk...r x)
, please output the full expansion.
Input Specification
The only line of input will contain a string in the form of (cijk...r x)
. It will contain no more than characters.
For of the points, the string will contain no more than characters.
Output Specification
Output a single line, the full expansion of the given function. Ensure that brackets are proper and that there is a space between the last cdr
or car
and the following x
. Other spacing will not matter.
Sample Input 1
(cadadr x)
Sample Output 1
(car (cdr (car (cdr x))))
Sample Input 2
(cdadaddr x)
Sample Output 2
(cdr (car (cdr (car (cdr (cdr x))))))
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