#include<bits/stdc++.h>
using namespace std;
const int N = 1e5 + 10;
int arr[N];
int n, k, ans;


bool check(int mid) {
    //分割刀数等于总段数-1
    int y = k-1;
    int cz = 0;
    for (int i = 1; i <= n; i++) {
        if (arr[i]+cz <= mid) {
            cz += arr[i];
        }
        else {
            cz = arr[i];
            y--;
        }
    }
    //如果刀数还剩那么肯定是合理的，还能找到更小的
    if (y >= 0) return 1;
    return 0;
}

void sc() {
    int l = 0, r = 1e9 + 10;
    while (l < r) {
        int mid = l + r >> 1;
        if (!check(mid)) l = mid+1;
        else r = mid;
    } 
    ans = r;
}

int main() {
    cin >> n >> k;
    for (int i = 1; i <= n; i++) cin >> arr[i];
    sc();
    cout << ans;
}