Christmas Party

CSESMathematicsOpen on judge ↗

There are n children at a Christmas party, and each of them has brought a gift. The idea is that everybody will get a gift brought by someone else. In how many ways can the gifts be distributed? Input The only input line has an integer n: the number of children. Output Print the number of ways modulo 10^9+7. Constraints - 1 \le n \le 10^6 Example Input: 4 Output: 9

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solution.cppC++17

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