func_code_string: #include <bits/stdc++.h>   using namespace std;   char CRTBUFF[30000];   struct debugger {     static void call(const char* it) {}     template <typename T, typename... aT>     static void call(const char* it, T a, aT... rest) {       string b;       for (; *it && *it !=  , ; ++it)         if (*it !=    ) b += *it;       cerr << b <<  =  << a <<    ;       call(++it, rest...);     }   };   int main() {     {       ios_base::sync_with_stdio(false);       cin.tie(NULL);     };     long long n, k, m, d, ans = 0, p, x;     cin >> n >> k >> m >> d;     for (int i = (0); i < (d); i += (1)) {       if (i > (n - 1) / k) continue;       long long p = i * k + 1, x = min(m, n / p);       ans = max(ans, x * (i + 1));     }     cout << ans << endl;   }   