// transport.cpp : Defines the entry point for the console application.
//

//#include "stdafx.h"
#include "fstream"
using namespace std;

int main()
{
	ifstream f("transport.in");
	ofstream g("transport.out");
	int n,nr,a[16000];
	f>>n>>nr;
	int i;
	int p=0,u=0;
	for(i=0;i<n;i++)
	{
		f>>a[i];
		if(p<a[i])
			p=a[i];
		u=u+a[i];
	}
	int sol=0;
	while(p<=u)
	{
		int m=(p+u)/2;
		int k=1,l=0;
		for(i=0;i<n;i++)
		{
			l+=a[i];
			if(l>m)
			{
				k++;
				l=a[i];
			}
			if(k>nr)
			{
				p=m+1;
				break;
			}
		}
		if(k<=nr)
		{
			u=m-1;
			sol=m;
		}
	}
	g<<sol;
	return 0;
}