func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     long long n, len, vf, va, k;     cin >> n >> len >> vf >> va >> k;     long long bl = (n + k - 1) / k;     double eff = static_cast<double>(va - vf) / (va + vf);     double koef = (va + (bl + (bl - 1) * eff - 1) * vf);     double ta = len / koef;     double ans = ta * (bl + (bl - 1) * eff);     cout << setprecision(15) << ans << endl;     return 0;   }   