#include<bits/stdc++.h>
using namespace std;
using ll = long long;

int main(){
  int N,M;
  cin >> N >> M;
  vector<ll> T(N);
  for(int i = 0; i < N; i++) cin >> T[i];
  
  priority_queue<pair<ll,ll>,vector<pair<ll,ll>>,greater<pair<ll,ll>>> pq;
  for(int i = 0; i < M; i++) pq.emplace(0LL,i);
  
  for(int i = 0; i < N; i++){
    auto[tmp,id] = pq.top();
    pq.pop();
    pq.emplace(tmp+T[i],id);
  }
  
  ll ans = 0;
  while(!pq.empty()){
    auto[tmp,id] = pq.top();
    pq.pop();
    ans = max(ans,tmp);
  }
  
  cout << ans << endl;
}