#include<bits/stdc++.h>
using namespace std;
long long n,k,a[100500]; 
int ans=0;
bool check(int x){
	int now=0;
	for(int i=1;i<=n;i++){
		now+=a[i]/x;
	}
	return now>=k;
}
signed main(){
	cin>>n>>k;
	for(int i=1;i<=n;i++){
		double x;
		cin>>x;
		a[i]=x*1000;
	}
	int l=0,r=1e9;
	while(r-l>=0.001){
		int mid=l+((r-l)>>1);
	//	cout<<l<<' '<<r<<" "<<mid<<"\n";
		if(check(mid)){
			ans=mid;
			l=mid+1;
		}else{
			r=mid-1;
		}
	}
	cout<<ans/1000.0;
	return 0;
}

奇怪的马蜂