Count Numbers C#

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

namespace ConsoleApp7
{
    class Program
    {
        static void Main(string[] args)
        {
            List<int> numbers = Console.ReadLine().Split(' ').Select(int.Parse).OrderBy(x => x).ToList();
            //int counter = 1;
            //Console.WriteLine(string.Join(" ", numbers));
            List<int> passed = new List<int>();
            for (int i = 0; i < numbers.Count(); i++)
            {
                if (!passed.Contains(numbers[i]))
                {
                    int counter = 0;
                    for (int j = 0; j < numbers.Count(); j++)
                    {
                        if (numbers[i] == numbers[j])
                        {
                            counter++;
                        }
                    }
                    Console.WriteLine($"{numbers[i]} -> {counter}");
                    passed.Add(numbers[i]);
                }
            }
        }
    }
}