func_code_string: #include <bits/stdc++.h>   using namespace std;   const int MAX = 100005;   const int oo = 1e9 + 7;   const long long mod = 1e9 + 7;   const double eps = 1e-11;   long long n;   int main() {     cin.sync_with_stdio(false);     cin.tie(0);     cin >> n;     cout << (n - 2LL) * (n - 2LL) << endl;   }   