538. Emoticons

Time limit per test: 1 second(s)
Memory limit: 262144 kilobytes
input: standard
output: standard

A berland national nanochat Bertalk should always stay up-to-date. That's why emoticons highlighting was decided to be introduced. As making emoticons to be highlighted is not exactly the kind of task one performs everyday but this task had to be done as soon as possible, the following simple rule was decided to be introduced: a round opening or closing bracket be considered part of an emoticon if:

If a bracket doesn't satisfy the conditions, it is considered a part of an emoticon. For example, let's consider the string "
Hi:) (it is me) I have bad news:-((
". In the string only the brackets that outline "
it is me
" aren't emoticons. Note that an opening bracket immediatelly followed by a closing bracket, i.e. "
", are not parts of emoticons by definition.

Your task is to print the number of brackets that are parts of emoticons in the given string.

The input data consist of a single non-empty string. The length of the string does not exceed 105 characters. The string consists of lowercase and uppercase Latin letters, spaces, round brackets and punctuation marks: "
", "
", "
", "
". The string does not begin with and does not end with a space.

Print a single number — the required number of brackets that are part of emoticons.

sample input
sample output
Hi:) (it is me) I have bad news:-((

sample input
sample output
((two plus two equals four)) 

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