func_code_string: #include <bits/stdc++.h>   using namespace std;   long long A[50];   int main() {     long long n;     A[0] = A[1] = 1;     scanf( %lld , &n);     for (long long i = 1; i <= 50; ++i) {       A[i] = A[i - 1] * i;     }     long long ans = A[n] / A[n / 2] / A[n / 2] / 2;     ans *= A[n / 2 - 1] * A[n / 2 - 1];     printf( %lld , ans);     return 0;   }   