#include <fstream>
using namespace std;
int main()
{
    ifstream fin ("transport.in");
    ofstream fout ("transport.out");
    int n,k,end=0,start=0,count,p=0,temp,mid=0;
    fin>>n>>k;
    int a[n];
    for(int i=0;i<n;i++)
    {
        fin>>a[i];
        end+=a[i];
        if(start<a[i]) start=a[i];
    }
    while(1)
    {
        mid=(start+end)/2;
        temp=mid;
        count=0;
        for(int i=0;i<n;i++)
        {
            temp-=a[i];
            if(temp<=0)
            {
                       if(temp<0)temp=mid-a[i];
                       else temp=mid;
                       count++;
            }
            if(temp>=0&&i==n-1) count++;
        }
        if(count>k)
        {
            start=mid+1;
        }
        else if(count==k)
        {
            p=mid;
            end=mid;
        }
        else if(count<k)
        {
            end=mid;
        }
        if(start>=end) break;
    }
    fout<<p;
}