#include <fstream>

using namespace std;

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

const int NMAX = 16005;

int v[NMAX], n, maxim, s;


int check(int k)
{
    int nr = 1, suma = 0;
    for(int i = 1; i <= n; i++)
    {
        if(suma + v[i] <= k)
        {
            suma += v[i];
        }
        else
        {
            suma = 0;
            nr++;
        }
    }
    return nr;
}

int cautbin(int x)
{
    int sol = s + 1, n2;
    for(n2 = 1; n2*2 < s; n2 *= 2)
    {
    }
    for(int i = n2; i > 0; i /= 2)
    {
        if(sol - i >= maxim && check(sol - i) <= x)
        {
            sol -= i;
        }
    }
    return sol;
}

int main()
{
    int m;
    fin >> n >> m;
    for(int i = 1; i <= n; i++)
    {
        fin >> v[i];
        maxim = max(maxim, v[i]);
        s += v[i];
    }
    fout << cautbin(m);
    return 0;
}