#include <fstream>

using namespace std;
ifstream in("transport.in");
ofstream out("transport.out");
int v[1000000];
int n,k;
int verificare(int c)
{
    int s=c,i,nrt=1;
    for(i=1; i<=n; i++)
    {
        if(s-v[i]<0)
        {
            nrt++;
            s=c;
        }
        s-=v[i];
    }
    return nrt;
}
int main()
{
    int i;
    in>>n>>k;
    int s=0;
    for(i=1; i<=n; i++)
    {
        in>>v[i];
        s=s+v[i];
    }
    int n2=1;
    while(n2*2<=s)
    {
        n2*=2;
    }
    int sol=s+1;
    for(i=n2; i>=1; i/=2)
    {
        if(sol-i>=1 && verificare(sol-i)<=k)
        {
            sol-=i;
        }
    }
    out<<sol;
    return 0;
}