#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;
}