#include <fstream>
using namespace std;
ifstream fin("transport.in");

ofstream fout("transport.out");
int v[16001],n,m,k,i,t,c,u,cc,s,p;
int main(){
    m=0;
    fin>>n>>k;
    for(i=1;i<=n;i++){
        fin>>v[i];
        if(v[i]>m)
            m=v[i];
    }
    p=m;
    u=16000*16000;
    while(p<=u){
        int mid = (p+u)/2;
        t=1;
        cc=mid-v[1];
        for(i=2;i<=n;i++)
            if(v[i]<=cc)
                    cc=cc - v[i];
            else{
                t++;
                cc=mid-v[i];
                }

        if(t<=k)
            u=mid-1;
        else
            p=mid+1;
    }
    fout<<p;
return 0;
}