#include <iostream>
#include <fstream>
#include <cmath>
#include <algorithm>
using namespace std;

ifstream fin("transport.in");
ofstream fout("transport.out");




int main()
{
   int n , klim , i, volmax = 0 ,st = 0;
   fin >> n >> klim;
   int v[n + 1];
   for (i = 1;i <= n;i++)
   {
       fin >> v[i];
       volmax += v[i];
       st = max(st,v[i]);                    //lower bound si volumul maxim

   }
   int dr = volmax , mid,cnt = 0;
   int kcurent = 1, chgvol = 0;
   int aux = log2(volmax) + 2;
   int ks[aux];

   while ( st < dr)
   {
       cnt++;
       mid = st + (dr - st)/2 ;
       kcurent = 1;
       chgvol = 0;

       for(i = 1; i <= n ; i++)
       {
         if((chgvol + v[i]) <= mid)
         {
             chgvol += v[i];

         }
           else
           {
               kcurent++;
               chgvol = v[i];

           }

       }
        ks[cnt] = kcurent;
        if(kcurent <= klim)
        {
            dr = mid;
        }
        else
        {
           st = mid + 1;

        }


   }
   fout << st << '\n';




    return 0;
}