/*

     题意：分成m个集合，使最大的集合值(求和)最小

     二分搜索：二分集合大小，判断能否有m个集合。

 */

 #include <cstdio>

 #include <algorithm>

 #include <cstring>

 #include <cmath>

 using namespace std;

 const int MAXN = 1e5 + ;

 const int INF = 0x3f3f3f3f;

 int a[MAXN];

 int n, m;

 bool check(int tot) {

     int j = , sum = ;

     for (int i=; i<=m; ++i)    {

         sum = ;

         while (j <= n && sum + a[j] <= tot)    {

             sum += a[j++];

         }

         if (j == n + ) return true;

     }

     return false;

 }

 int main(void)  {       //POJ 3273 Monthly Expense

     //freopen ("POJ_3273.in", "r", stdin);

     while (scanf ("%d%d", &n, &m) == ) {

         int l = , r = ;

         for (int i=; i<=n; ++i)    {

             scanf ("%d", &a[i]);

             if (l < a[i])   l = a[i];

             r += a[i];

         }

         while (l < r)   {

             int mid = (l + r) >> ;

             if (check (mid))    r = mid;

             else    l = mid + ;

         }

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

     }

     return ;

 }