#include<fstream>
#define nx 16007
using namespace std;
int n,k,i,x,s,d,m,sol,v[nx*nx];

ifstream fin("transport.in");
ofstream fout("transport.out");

int verificare()
{
    int mid=0,p=k,x=0;

    while(p && x<v[n])
    {
        int s=1,d=n;
        x=v[mid]+m;

        p--,mid=0;
        while(s<=d)
        {
            mid=(s+d)/2;
            if(v[mid]<=x)s=mid+1;
            else d=mid-1;
        }
        if(v[mid]>x)mid--;
    }

    if(x<v[n])return 0;
    return 1;
}

int main()
{
    fin>>n>>k;
    for(i=1;i<=n;i++)
    {
        fin>>x;
        if(x>s)s=x;
        v[i]=v[i-1]+x;
    }

    d=v[n];
    while(s<=d)
    {
        m=(s+d)/2;
        if(verificare())
        {
            sol=m;
            d=m-1;
        }
        else s=m+1;
    }

    fout<<sol;
    return 0;
}