func_code_string: #include <bits/stdc++.h>   using namespace std;   void solve() {     long long n;     cin >> n;     if (n % 2)       cout << setprecision(0) << fixed <<  -  << ceil((1.0 * n) / 2) <<   n ;     else       cout << fixed << n / 2 <<   n ;   }   int main() { solve(); }   