#include <cstdio>

int n,a[1<<16],k;

int transp(int q)
{
	int x,nr=0;
	for (int i=1;i<=n;i++)
		if (x+a[i]<q)
		{
			x+=a[i];
		}
		else
		{
			nr++;
			x=a[i];
		}
	if (nr<=k)
		return 1;
	return 0;
}

int caut(int p)
{
	int i,pas=(1<<16);
	for (i=0;pas;pas>>=1)
		if (transp(i+pas)==0)
			i+=pas;
	return i;
}

int main()
{
	freopen("transport.in","r",stdin);
	freopen("transport.out","w",stdout);
	scanf("%d%d",&n,&k);
	for (int i=1;i<=n;i++)
		scanf("%d",&a[i]);
	printf("%d",caut(k));
	return 0;
}