#include <bits/stdc++.h>
using namespace std;
 
long long solve(int n, vector<int>v, int m){
	priority_queue<long long>pq;
	sort(v.begin(),v.end());
	for(int i=0; i<min(n,m); i++){
		pq.push(-v[i]);
	}
	for(int i=m; i<min(n,m); i++){
		int val=-pq.top()+v[i];
		pq.pop();
		pq.push(-val);
	}
	long long ans=0;
	while(!pq.empty()){
		ans=max(ans,-pq.top());
		pq.pop();
	}
	return ans;
}
 
int main() {
	int n, m;
	cin>>n>>m;
	vector<int>v(n);
	for(int i=0; i<n; i++){
		cin>>v[i];
	}
	cout<<solve(n,v,m);
	return 0;
}

I2luY2x1ZGUgPGJpdHMvc3RkYysrLmg+CnVzaW5nIG5hbWVzcGFjZSBzdGQ7Cgpsb25nIGxvbmcgc29sdmUoaW50IG4sIHZlY3RvcjxpbnQ+diwgaW50IG0pewoJcHJpb3JpdHlfcXVldWU8bG9uZyBsb25nPnBxOwoJc29ydCh2LmJlZ2luKCksdi5lbmQoKSk7Cglmb3IoaW50IGk9MDsgaTxtaW4obixtKTsgaSsrKXsKCQlwcS5wdXNoKC12W2ldKTsKCX0KCWZvcihpbnQgaT1tOyBpPG1pbihuLG0pOyBpKyspewoJCWludCB2YWw9LXBxLnRvcCgpK3ZbaV07CgkJcHEucG9wKCk7CgkJcHEucHVzaCgtdmFsKTsKCX0KCWxvbmcgbG9uZyBhbnM9MDsKCXdoaWxlKCFwcS5lbXB0eSgpKXsKCQlhbnM9bWF4KGFucywtcHEudG9wKCkpOwoJCXBxLnBvcCgpOwoJfQoJcmV0dXJuIGFuczsKfQoKaW50IG1haW4oKSB7CglpbnQgbiwgbTsKCWNpbj4+bj4+bTsKCXZlY3RvcjxpbnQ+dihuKTsKCWZvcihpbnQgaT0wOyBpPG47IGkrKyl7CgkJY2luPj52W2ldOwoJfQoJY291dDw8c29sdmUobix2LG0pOwoJcmV0dXJuIDA7Cn0=

NAoyIDggNyAxMAoz

4
2 8 7 10
3