#include <fstream>
using namespace std;

const int NMAX = 16000;
int v[NMAX + 5];
int n ,k;
ifstream fin("transport.in");
ofstream fout("transport.out");

int ok(int c){

int tr,s,i;
for(i=1;i<=n;++i){
if(v[i]>c)return k+1 ;
s+= v[i];
if(s > c){
    tr++;
    s = v[i];
}
    }
if(s>0)tr++;
return tr;
}

int bs(int st,int dr){
 int med,last = -1;
 while(st <= dr){
    med = (st+dr)/2;
    if (ok(med) <= k){
    last = med;
    dr = med-1;}
    else st=med+1;
 }

return last;

}




int main()
{
    int i,vmax;
    fin >> n >> k;
    vmax = 0;
    for(i=1;i<=n;++i){fin >> v[i];vmax+=v[i];}
    fout << bs(1,vmax);
    return 0;
}