#include <cstdio>
using namespace std;
int N, M, A[100000000];
bool judge(int x)
{
int sum = 0, count = 0;
for (int i = 0; i < N; i++)
{
if (sum + A[i] <= x)
{
sum += A[i];
}
else
{
count++;
sum = A[i];
}
}
return ++count <= M;
}
int main()
{
scanf("%d%d", &N, &M);
for (int i = 0; i < N; i++)
scanf("%d", &A[i]);
int left = 1, right = 1e9;
while (left < right)
{
int mid = (left + right) / 2;
if (judge(mid))
right = mid;
else
left = mid + 1;
}
printf("%d", left);
return 0;
}