#include<iostream>
using namespace std;
#define MAX 100000
typedef long long llong;
int n, k;
llong T[MAX];

int check(llong p){
  int i = 0;
  for(int j = 0 ; j < k ; j++){
    llong s = 0;
    while(s + T[i] <= p){
      s += T[i];
      i++;
      if(i == n) return n;
    }
  }
  return i;
}

int solve(){
  llong left = 0;
  llong right = 100000 * 10000;
  llong mid;
  while(right - left > 1){
    mid = (left + right) / 2;
    int v = check(mid);
    if(v >= n) right = mid;
    else left = mid;
  }

  return right;
}

main(){
  cin >> n >> k;
  for(int i = 0 ; i < n ; i++){
    cin >> T[i];
  }
  llong ans = solve();
  cout << ans << endl;
}

