#include <iostream>
#include <fstream>

using namespace std;

ifstream fin("transport.in");
ofstream fout("transport.out");
int n,k,i,s,st,dr,mid,maxim,r,j;

int main()
{
    fin >> n >> k;
    int v[n+5];
    for (i=1;i<=n;i++){
       fin >> v[i];
       s=s+v[i];
       if (v[i]>maxim){
           maxim=v[i];
       }
    }
    st=maxim;
    dr=s;
    while (st<=dr){
        mid=(st+dr)/2;
        j=1;
        r=mid-v[1];
        for (i=2;i<=n;i++){
            if (v[i]<=r){
                r=r-v[i];
            }
            else{
                j++;
                r=mid-v[i];
            }
        }
        if (j<=k){
            dr=mid-1;
        }
        else{
            st=mid+1;
        }
    }
    fout << st;
    return 0;
}