#include <iostream>
#include <vector>
#include <algorithm>
//基本策略->
//二分查找 mid = (low + high) / 2
//贪婪验证 是否存在分组方式 
 
using namespace std;

bool check(const vector<int>& a, int target, int k) {
    int js = 1;   // 当前分配了1个抄写员
    int temp = 0; // 当前抄写员工作量

    for (int i = 0; i < a.size(); i++) {
        if (a[i] > target) return false; // 单个书页超过 target，不可行
        if (temp + a[i] > target) { // 超过 target，换一个抄写员
            js++;
            temp = a[i];
        } else {
            temp += a[i];
        }
    }

    return js <= k; // 是否可行
}

int main(){
	int n, k;
	cin >> n >> k;
	vector<int> arr;
	arr.resize(n);
	
	int max = 0;
	int sum = 0;
	for(int i = 0; i < n; i++){
		cin >> arr[i];
		if(max < arr[i]) max = arr[i]; 
		sum += arr[i];
	}
		
	int left = max;
    int right = sum;
    int result = right;

    while (left <= right) {
        int mid = left + (right - left) / 2;
        if (check(arr, mid, k)) {
            result = mid;
            right = mid - 1;
        } else {
            left = mid + 1;
        }
    }

    cout << result << endl;

	return 0;
}