Miscellaneous [I]
You want to know how many ways you can organise (
and )
brackets so the result string is balanced, that is, so that every closing )
bracket is preceded by an accompanying opening (
bracket somewhere earlier in the string.
Examples of all valid organisations with :
((()))
()()()
(())()
()(())
(()())
Examples of invalid organisations with :
())(()
)()()(
(()))(
Input
Input will consist of a single integer , representing the number of open and closed brackets we want to organise
Output
Output should be a single integer, representing the number of unique strings of balanced parenthesis of length . Since this number could be quite large, output the answer modulo
Constraints
Example
Input
3
Output
5
Input
10
Output
16796
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