Parsa, a Computer Science graduate, works as a typist. However, he has an unusual habit—whenever he makes a mistake while typing, instead of pressing the Backspace key, he mistakenly presses the =
key.
You are given a string , which represents what Parsa actually typed. Your task is to determine the string
, which represents what he intended to type. The rules for correction are as follows:
- A
=
character erases the rightmost character before it appeared which is not a=
(if any) - Leading
=
characters do nothing (since there is nothing to erase)
Your goal is to reconstruct from
and print it.
Input
In the only line of input you have the string , which is what Parsa wrote with his keyboard.
It is guaranteed that only contains small English letters and the character
=
.
Output
Print what Parsa intended to type.
Constraints
Example 1
Input
testtwoo===wo
Output
testtwo
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