#include <iostream>

using namespace std;
const int N = 1e5 + 10;

int n, m;
int a[N];

bool check(int mid)
{
    //sum 代表天数  res 代表当前财政数额
    int sum = 1, res = 0;
    for (int i = 1; i <= n; i++)
    {
        if (res + a[i] <= mid)
            res += a[i];
        else
            sum++, res = a[i];
        if (sum > m) return false;
    }
    return true;
}


int main()
{
    int l = 1, r = 1e9;
    scanf("%d%d", &n, &m);
    for (int i = 1; i <= n; i++)
    {
        scanf("%d", &a[i]);
        l = max(l, a[i]);
    }
    //找左边界
    while (l < r)
    {
        int mid = l + r >> 1;
        if (check(mid)) r = mid;
        else l = mid + 1;
    }
    cout << l;
    return 0;
}