#include <cstdio>

using namespace std;
const int NMAX=16000;
int v[NMAX+5];//64020B
int n,k;

bool ok(int c)
{
    int i,sc,tr;
    sc=tr=0;
    for(i=1;i<=n;i++)
    {
        if(v[i]>c)
            return 0;
        if(sc+v[i]<=c)
            sc=sc+v[i];
        else
        {
            tr++;
            sc=v[i];
        }
    }
    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()
{
    freopen("transport.in","r",stdin);
    freopen("transport.out","w",stdout);
    int i, s;
    scanf("%d%d",&n,&k);
    s=0;
    for(i=1;i<=n;i++)
    {
        scanf("%d",&v[i]);
        s=s+v[i];
    }
    printf("%d",bsL(1,s));
    return 0;
}