#include <vector>
#include <iostream>
#include <algorithm>
#include <map>
#include <utility>
#include<iostream>
#include<queue>
#include<utility>
#define RRR ios_base::sync_with_stdio(false);cin.tie(0);
#define ll long long
#define int ll
#define pp pair<int,int>
using namespace std;
vector<int> ar;
int n;
 int k;
 int i;
bool check(int c)
{
	int s = 0;
	int j = 0;
	for ( i=0;i<n && j<k;i++)
	{
		if (s+ar[i] < c)
		{
			s += ar[i];
		}
		else 
		{
			if (s != 0)
			{
				s = 0;
				j++;
				i--;
			}
			else return 0;
		}
	}
	if (i < n || j > k )
		return 0;
	return 1;
}


int32_t main()
{
	RRR
	//		freopen("text.txt","r",stdin);
			freopen("transport.in","r",stdin);
	freopen("transport.out","w",stdout);
	
   
	cin >> n >> k;
	
	
	for (int i=0;i<n;i++)
	{
			int z;
			cin >> z;
			ar.push_back(z);
	} 
	//sort(ar.begin(),ar.end());
	int m;
	int l = 1;
	int high = 1600*1600;
	while (l <= high)
	{
		m = (l+high)/2;
		if (check(m))
			high = m-1;
		else l = m+1;
	}
	cout << high;
	return 0;

}