Tubes

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

namespace _3.Tubes
{
    class Tubes
    {
        static void Main(string[] args)
        {
            int n = int.Parse(Console.ReadLine());
            int m = int.Parse(Console.ReadLine());

            int[] tubes = new int[n];
            for (int i = 0; i < n; i++)
            {
                tubes[i] = int.Parse(Console.ReadLine());
            }

            bool haveSolution = false;
            int solutionLength = -1;
            int cutDownBorder = 0;
            int cutUpBorder = tubes.Max();
            int cutLength = cutUpBorder + cutDownBorder / 2;

            while (cutUpBorder - cutDownBorder > 1)
            {
                haveSolution = false;
                int tubeItems = 0;

                for (int j = 0; j < n; j++)
                {
                    tubeItems += tubes[j] / cutLength;
                    if (tubeItems >= m)
                    {
                        solutionLength = cutLength;
                        haveSolution = true;
                        break;
                    }
                }
                if (haveSolution)
                {
                    cutDownBorder = cutLength;
                }
                else
                {
                    cutUpBorder = cutLength;
                }
                cutLength = (cutUpBorder + cutDownBorder) / 2;
            }

            Console.WriteLine(solutionLength);
        }
    }
}