using System;
using System.Linq;
using System.Collections.Generic;

namespace Algorithm
{
    class Program
    {
        static void Main(string[] args)
        {
            var N = int.Parse(Console.ReadLine());
            var L = Console.ReadLine().Split().Select(int.Parse).ToArray();
            var K = long.Parse(Console.ReadLine());

            var ng = 0D;
            var ok = 1000000000D;

            for (var i = 0; i < 100; i++)
            {
                var mid = (double)((ok + ng) / 2);
                var tmp = 0L;
                for (var j = 0; j < N; j++)
                    tmp += (long)(L[j] / mid);

                if (tmp >= K) ng = mid;
                else ok = mid;
            }

            Console.WriteLine(ng);

        }
    }
}