#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; typedef long long ll; int n; double *len; ll k; bool check(double x) { ll cnt = 0; for (int i = 0; i < n; i++) { cnt += floor(len[i]/x); if (cnt >= k) return true; } return false; } int main() { cin >> n; len = new double[n]; for (int i = 0; i < n; i++) cin >> len[i]; cin >> k; double l, r; l = 0; r = 1e10; while (abs(l-r) >= 1e-10) { double p = (l+r)/2; if (!check(p)) { r = p; }else { l = p; } } printf ("%.10f\n", l); }