#include<bits/stdc++.h>
using namespace std;

int main(){
	int n,k; cin>>n>>k;
	vector<int>val(n); for(auto&&i:val)cin>>i;
	sort(val.rbegin(),val.rend());
	int ans=0;
	for(int i=0,mx=0;i<n;++i){
		mx+=val.at(i);
		int mn=0;
		for(int j=n-1;j>=0&&j-i>k-2;--j){
			mn+=val.at(j);cout<<mx<<" "s<<mn<<"\n"s;
			ans=max(ans,(int)ceil((double)mx/(i+1)-(double)mn/(n-j)));
		}
	}
	cout<<ans<<"\n"s;
}