#include <iostream> 
#include <cstdio> 
#include <cstdlib> 
using namespace std; 
int a[100010],s[100010];
int main(void) 
{ freopen("seqa.in","r",stdin); 
freopen("seqa.out","w",stdout); 
int i,n,k,l,r,mid,c,last; 
bool ok; 
cin>>n>>k; 
for (i=1;i<=n;i++) { cin>>a[i];
s[i]=s[i-1]+a[i]; 
} l=0; r=s[n];
mid=r>>1;
while (l<r) { ok=true; 
last=0; c=0; 
for (i=1;i<=n;i++) 
{ 
	if (s[i]-s[last]>mid) 
	{ 
		i--; c++; if (c>=k) 
		{ 
			ok=false; 
			break; 
		} last=i; 
	} 
} 
if (ok) 
{ 
	r=mid; 
	mid=(l+r)>>1; 
} 
else 
{
	l=mid+1;
	mid=(l+r)>>1; 
} 
} cout<<mid<<endl; return(0); }