#include <iostream>
#include <string.h>
using namespace std;
const int N = 1e5 + 10;
const int INF = 0x3f3f3f3f;
long long n , k;
int a[N];
bool cheak(int x)
{
	int ans = 1 , sum = 0;
	for(int i = 1 ; i <= n ; i++)
	{
		sum += a[i];
		if(sum > x)
		{
			ans++;
			sum = a[i];
		}
	}
	return ans <=  k;
}
int main()
{
	cin >> n >> k;
	int l , r;
	l = 0 , r = 0;
	for(int i = 1 ; i <= n ; i++)
	{
		cin >>a[i];
		r += a[i];
		l = max(l , a[i]);
	}
	while(l < r)
	{
		int mid = l + r >> 1;
		if(cheak(mid))
			r = mid;
		else
			l = mid + 1;
	}
	cout << r << endl;
	return 0;
}