#include <iostream>
using namespace std;


int L[10005];


int main()
{
	int N, K, num, lb = 0, rb = 1, mid;
	double c;

	cin >> N >> K;

	for (int i = 0; i < N; i++)
	{
		cin >> c;
		L[i] = (int)(c * 10000 + 0.1);
		if (L[i] > rb)
		{
			rb = L[i];
		}
	}

	while (rb - lb > 1)
	{
		mid = (lb + rb) >> 1;
		num = 0;

		for (int i = 0; (i < N) && (num < K); i++)
		{
			num += (L[i] / mid);
		}

		if (num >= K)
		{
			lb = mid;
		}
		else
		{
			rb = mid;
		}
	}

	lb = (lb + 5) / 100;

	cout << lb / 100 << '.' << (lb % 100) / 10 << lb % 10 << '\n';

	return 0;
}