#include<bits/stdc++.h>
using namespace std;
const int N = 1e5+5;
#define LL long long
#define F(i,a,b) for(int i=a;i<=b;i++)
int a[N],ans,n,m;
bool check(int mid)
{
    int sum = 0,cnt = 1;
    for(int i = 1;i<=n;i++)
    {
        if(a[i] > mid) return 0;
        if(sum + a[i] <= mid)
            sum += a[i];
        else
        {
            cnt++;
            sum = a[i];
        }
    }
    return cnt <= m;
}
int main()
{
    cin>>n>>m;
    for(int i = 1;i<=n;i++) cin>>a[i];
    int l = 0,r = 1e9;
    while(l <= r)
    {
        int mid = l+r>>1;
        if(check(mid))
        {
            ans = mid;
            r = mid-1;
        }
        else l = mid+1;
    }
    cout<<ans<<'\n';
    return 0;
}