Calculating density of characters and printing them in hi-to-low manner

chardensitycalc.cs

/*
sample input : aazzaaffggghhtzzz
sample output : zzzzzaaaagggffhht

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

namespace task1
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Въведете низ :");
            var text = Console.ReadLine();
            var list = new Dictionary<char, int>();
            for (int i = 0; i < text.Count(); i++)
            {
                
                if (!list.ContainsKey(text[i]))
                {
                    var num = text.Where(x => x.Equals(text[i])).Count();
                    list.Add(text[i], num);
                }
               
            }
 
            foreach (var i in list.OrderByDescending(x => x.Value))
            {
                for (int j = 0; j < i.Value; j++)
                {
                    Console.Write(i.Key);
                }
                
            }
            Console.ReadLine();
        }
    }
}

linq?

what about linq ?

I just answer myself after viewing the imports in begging after writing the comment :)