func_code_string: #include <bits/stdc++.h>   using namespace std;   void err(istream_iterator<string> it) {}   template <typename T, typename... Args>   void err(istream_iterator<string> it, T a, Args... args) {     cerr << *it <<   =   << a << endl;     err(++it, args...);   }   long long powMod(long long x, long long y) {     long long p = 1;     while (y) {       if (y % 2) {         p = (p * x) % ((long long)1e9 + 7);       }       y /= 2;       x = (x * x) % ((long long)1e9 + 7);     }     return p;   }   long long CpowMod(long long x, long long y, long long w) {     long long p = 1;     while (y) {       if (y % 2) {         p = (p * x) % w;       }       y /= 2;       x = (x * x) % w;     }     return p;   }   long long invMod(long long x) { return powMod(x, ((long long)1e9 + 7) - 2); }   long long CinvMod(long long x, long long w) { return CpowMod(x, w - 2, w); }   long long gcd(long long a, long long b) { return b == 0 ? a : gcd(b, a % b); }   void solve() {     long long n;     cin >> n;     long long ans = 1;     for (long long i = 1; i <= n - 1; i++) {       if (i != n / 2) ans *= i;     }     cout << ans << endl;   }   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     cout.precision(20);     solve();     return 0;   }   