#include <fstream>
using namespace std;
const int NMAX=16000;
int n,k;
int v[NMAX+5];
ifstream fin("transport.in");
ofstream fout("transport.out");
bool ok(int C)
{
int i,tr,sum;
tr=sum=0;
for(i=1;i<=n;++i)
{
if(v[i]>C)
return 0;
if(sum+v[i]<=C)
sum=sum+v[i];
else
{
tr++;
sum=v[i];
}
}
if(sum>0)
tr++;
return (tr<=k);
}
int bsL(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()
{
int s,i,ans;
fin>>n>>k;
s=0;
for(i=1;i<=n;++i)
{
fin>>v[i];
s=s+v[i];
}
ans=bsL(1,s);
fout<<ans<<"\n";
return 0;
}