#include <iostream>
#include <cstdio>
using namespace std;
const double eps = 1e-3;
const int N = 1e5 + 5;
int n, m;
double arr[N];
bool check(double length)
{
int num = 0;
for (int i = 0; i < n; ++i) num += (int)(arr[i] / length);
return num >= m;
}
int main()
{
scanf("%d%d", &n, &m);
for (int i = 0; i < n; ++i) scanf("%lf", &arr[i]);
double l = 0, r = 1e9;
while (r - l > eps)
{
double mid = (l + r) / 2.0;
if (check(mid)) l = mid;
else r = mid;
}
printf("%.2lf", r);
return 0;
}