BZOJ1430 小猴打架

娱乐向题目

ans = (n - 1) ! * n ^ (n - 2)...没了

/**************************************************************
    Problem: 1430
    User: rausen
    Language: C++
    Result: Accepted
    Time:188 ms
    Memory:804 kb
****************************************************************/
 
#include <cstdio>
 
using namespace std;
const int mod = 9999991;
 
int i, n;
long long x = 1;
 
int main() {
    scanf("%d
", &n);
    for (i = 1; i < n - 1; ++i)
        (x *= n) %= mod;
    for (i = 1; i < n; ++i)
        (x *= i) %= mod;
    printf("%lld
", x);
    return 0;
}