Bracket Sequences I

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Your task is to calculate the number of valid bracket sequences of length n. For example, when n=6, there are 5 sequences: - ()()() - ()(()) - (())() - ((())) - (()()) Input The only input line has an integer n. Output Print the number of sequences modulo 10^9+7. Constraints - 1 \le n \le 10^6 Example Input: 6 Output: 5

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solution.cppC++17

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