#include <cstdio>

using namespace std;

int n,v[16005],k;

bool incerc(int c){
    //return 1 daca nr de timp <=k sau 0 in caz contrar
    int s,p;
    s=0;
    p=0;
    for(int i=1;i<=n;i++){
        if(v[i]>c)
            return 0;
            if(s+v[i]>c){
                p++;
                s=v[i];
            }
            else
                s=s+v[i];
    }
    if(s>0)
        p++;
    if(p<=k)
        return 1;
    else
        return 0;
}

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

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