// Made by Alex Prohnitchi

#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>

typedef long long ll;

const ll mod=1e9+7;

const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};
const int N=100000;
#define all(x) x.begin(),x.end()
#define allr(x) x.rbegin(),x.rend()
#define rc(x)  return cout<<x<<"\n",0
#define sz(s)  (int) s.size()
#define pb push_back
#define mp make_pair
#define fr first
#define sc second
#define PI 3.14159265358979

using namespace std;

ll t;
ll a[N],n,k;
bool verificare(int x) {
	ll count=0,ver=1;
	for (int i=1; i<=n; i++) {
		if (a[i]>x)return false;
		count+=a[i];
		if (count>x) {
			ver++;
			count=a[i];
		}
	}
	return (ver<=k);
}
int main() {
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	ifstream cin("transport.in");
	ofstream cout("transport.out");
	cin >> n >> k;
	ll mx=-2e6;
	for (int i=1; i<=n; i++) {
		cin >> a[i];
		mx=max(mx,a[i]);
	}
	ll ans;
	ll l=mx,r=n*mx,mid;
	while (l<=r) {
		mid=l+(r-l)/2;
		if (verificare(mid)) {
			ans=mid;
			r=mid-1;
		}
		else {
			l=mid+1;
		}
	}
	cout << ans << '\n';
}