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CF1132A.Regular Bracket Sequence
Regular Bracket Sequence
A string is called bracket sequence if it does not contain any characters other than "(" and ")". A bracket sequence is called regular if it it is possible to obtain correct arithmetic expression by inserting characters "+" and "1" into this sequence. For example, "", "(())" and "()()" are regular bracket sequences; "))" and ")((" are bracket sequences (but not regular ones), and "(a)" and "(1)+(1)" are not bracket sequences at all.
You have a number of strings; each string is a bracket sequence of length . So, overall you have strings "((", strings "()", strings ")(" and strings "))". You want to write all these strings in some order, one after another; after that, you will get a long bracket sequence of length . You wonder: is it possible to choose some order of the strings you have such that you will get a regular bracket sequence? Note that you may not remove any characters or strings, and you may not add anything either.
Input
The input consists of four lines, -th of them contains one integer ().
Output
Print one integer: if it is possible to form a regular bracket sequence by choosing the correct order of the given strings, otherwise.
Note
In the first example it is possible to construct a string "(())()(()((()()()())))", which is a regular bracket sequence.
In the second example it is possible to construct a string "", which is a regular bracket sequence.
Samples
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