#include <cstdio>
#include <algorithm>
using namespace std;
int v[16010],n,k;
int incerc(int x)
{
    int i,ocupat,tran;
    ocupat=0;tran=1;
    for(i=1;i<=n;i++)
    {
        if(ocupat+v[i]<=x)
        {
            ocupat+=v[i];
        }
        else
        {
            ocupat=v[i]; tran++;
        }
        if(v[i]>x)
            return 0;
    }
    if(tran>k)
        return 0;
    else
        return 1;
}
int bs_left(int st,int dr)
{
    int med,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()
{
    int i ,s=0;
    freopen("transport.in","r",stdin);
    freopen("transport.out","w",stdout);
    scanf("%d%d",&n,&k);
    for(i=1;i<=n;i++)
    {
        scanf("%d",&v[i]);
        s+=v[i];
    }
    printf("%d",bs_left(1,s));
    return 0;
}