#include <bits/stdc++.h>
using namespace std;
int v[16005],n,k;
bool ok(int c)
{
	int i,tr,sc;
	sc=tr=0;
	for(i=1;i<=n;i++)
	{
		if(v[i]>c) return 0;
		if(sc+v[i]<=c)
			sc=sc+v[i];
		else
		{
			tr++;
			sc=v[i];
		}
	}
	if(sc>0) tr++;
	return tr<=k;
}
int bs_left(int st, int dr)
{
	int med,last=-1;
	while(st<=dr)
	{
		med=(st+dr)/2;
		if(ok(med))
		{
			last=med;
			dr=med-1;
		}
		else st=med+1;
	}
	return last;
}
int main()
{
	freopen("transport.in","r",stdin);
	freopen("transport.out","w",stdout);
    int s=0;
    cin>>n>>k;
    for(int i=1;i<=n;i++)
    {
    	cin>>v[i];
    	s=s+v[i];
    }
    cout<<bs_left(1,s);
    return 0;
}