#include <cstdio>

using namespace std;

const int NMAX=16000;
int v[NMAX+5];//4MB
int n,k;
bool ok(int c){
    int tr,i,sc;
    tr=sc=0;
    for(i=1;i<=n;++i){
        if(v[i]>c){
            return 0;
        }
        if(sc+v[i]<=c){
            sc+=v[i];
        }else{
            ++tr;sc=v[i];
        }
    }
    if(sc>0){
        ++tr;
    }
    return tr<=k;
}

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

int main(){
    freopen("transport.in","r",stdin);
    freopen("transport.out","w",stdout);
    int i,smax;
    smax=0;
    scanf("%d%d",&n,&k);
    for(i=1;i<=n;++i){
        scanf("%d",&v[i]);
        smax+=v[i];
    }
    printf("%d",bs_left(1,smax));
    return 0;
}