#include <iostream>

 #include <cstdio>

 using namespace std;

 int n, m, a[], x, y, ans = ;

 bool pd(int mid)

 {

     int i, sum = , tot = ;

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

     {

         sum += a[i];

         if(sum > mid)//分段数+1

         {

             sum = a[i];

             tot++;

         }

     }

     if(tot > m) return ;

     return ;//如果是小于m的话也还可以再分

 }

 int main()

 {

     int i, j, mid;

     scanf("%d %d", &n, &m);

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

     {

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

         x = max(x, a[i]);//答案最小

         y += a[i];//答案最大

     }

     while(x <= y)

     {

         mid = (x + y) >> ;

         if(pd(mid)) y = mid - ;

         else x = mid + ;

     }

     printf("%d", x);

     return ;

 }