CF223A Bracket Sequence

A bracket sequence is a string, containing only characters "(", ")", "\[" and "\]". A correct bracket sequence is a bracket sequence that can be transformed into a correct arithmetic expression by inserting characters "1" and "+" between the original characters of the sequence. For example, bracket sequences "()\[\]", "(\[\])" are correct (the resulting expressions are: "(1)+\[1\]", "(\[1+1\]+1)"), and "\](" and "\[" are not. The empty string is a correct bracket sequence by definition. A substring $ s[l...\ r] $ $ (1

The first and the only line contains the bracket sequence as a string, consisting only of characters "(", ")", "\[" and "\]". It is guaranteed that the string is non-empty and its length doesn't exceed $ 10^{5} $ characters.

In the first line print a single integer — the number of brackets «\[» in the required bracket sequence. In the second line print the optimal sequence. If there are more than one optimal solutions print any of them.