#include <cstdio>
using namespace std;
int v[16001];
int n,t;
bool incerc (int c)
{
    int s=0,smax=1,i;
    for (i=1;i<=n;i++)
    {
        if (s+v[i]<=c)
           s=s+v[i];
        else
        {
            smax++;
            s=v[i];
        }
    }
    if (smax<=t)
        return 1;
    return 0;
}
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()
{
    freopen("transport.in","r",stdin);
    freopen("transport.out","w",stdout);
    int i,s;
    scanf("%d%d",&n,&t);
    for (i=1;i<=n;i++)
    {
        scanf("%d",&v[i]);
        s=s+v[i];
    }

    printf("%d",bs_left(1,s));
    return 0;
}