Problem Description

Consider a simple regular expression:

A regular expression consists only of x, (, ), and |.

Xiaoming wants to find the length of the longest string that this regular expression can accept.

For example, ((xx|xxx)x|(x|xx))xx can accept the longest string xxxxxx, whose length is $6$.

Input Format

A regular expression made up of x()|. The input length does not exceed $100$, and it is guaranteed to be valid.

Output Format

Output the length of the longest string that this regular expression can accept.

((xx|xxx)x|(x|xx))xx  

6

Hint

Lanqiao Cup 2022 Provincial Contest Group A, Problem G.

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