using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        var t = NList;
        var pq = new PriorityQueue<Server, Server>();
        for (var i = 0; i < c[1]; ++i)
        {
            var s = new Server(i);
            pq.Enqueue(s, s);
        }
        foreach (var ti in t)
        {
            var cur = pq.Dequeue();
            cur.Weight += ti;
            pq.Enqueue(cur, cur);
        }
        var ans = 0L;
        while (pq.Count > 0)
        {
            var cur = pq.Dequeue();
            ans = Math.Max(ans, cur.Weight);
        }
        WriteLine(ans);
    }
    class Server : IComparable<Server>
    {
        public int Id;
        public long Weight;
        public Server(int id, long weight = 0)
        {
            Id = id; Weight = weight;
        }
        public int CompareTo(Server other)
        {
            var d = Weight.CompareTo(other.Weight);
            if (d != 0) return d;
            return Id.CompareTo(other.Id);
        }
    }
}