#include <fstream>
using namespace std;
ifstream fin("transport.in");
ofstream fout("transport.out");
int i,v[20000],n,k,j,a,maxi,mini=160000,ok,t,c;
int main()
{
    fin>>n>>k;
    for(i=1;i<=n;i++)
    {
        fin>>v[i];
        maxi+=v[i];
        mini=min(mini,v[i]);
    }
    while(maxi>mini)
    {
        a=maxi+mini;
        a/=2;
        t=0;
        c=a;
        for(i=1;i<=n;i++)
        {
            if(v[i]>c)
            {
                t++;
                c=a-v[i];
            }
            else
                if(v[i]<c)
                    c-=v[i];
                else
                    t++,c=a;
        }
        if(c!=a)
            t++;
        if(t>k)
            if(mini+1==maxi)
                {fout<<mini;return 0;}
            else
                mini=a+1;
        else
        if(mini+1==maxi)
                {fout<<mini;return 0;}
            else
            maxi=a-1;
    }
    fout<<maxi;
    return 0;
}