poj3273

//556k, 63ms
#include <iostream>
#include <algorithm>
#include <numeric>

using namespace std;

const int MAX_N = 100005;

int n, m;
int money[MAX_N];

bool C(int d) {
    int expense = 0;
    int months = 1;
    for(int i=0; i<n; i++) {
        expense = expense  + money[i];
        if(expense > d) {
            expense = money[i];
            months++;   
        }
    }

    if(months > m)  return true;

    return false;
}

int main() {



    scanf("%d%d", &n, &m);
        for(int i=0; i<n; i++)
            scanf("%d", &money[i]);
        int lb = *max_element(money, money+n);
        int ub = accumulate(money, money+n, 0);

        while(lb < ub) {
            int mid = (lb + ub) / 2;
            if(C(mid)) {
                lb = mid + 1;
            }
            else {
                ub = mid;
            }
        }

        printf("%d\n", lb);


    return 0;
}