Kolejka by Stos

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

namespace zad2
{
    class Kolejka
    {
        Stack<int> a = new Stack<int>();
        Stack<int> b = new Stack<int>();

        public void Dodaj(int n)
        {

            a.Push(n);
        }

        public int Usun()
        {
            if (b.Count == 0)
            {
                while(a.Count > 0)
                    b.Push(a.Pop());
            }

            return b.Pop();
        }

        public int Rozmiar()
        {
            return a.Count + b.Count;
        }
    }


    class Program
    {
        static void Main(string[] args)
        {
            Kolejka k = new Kolejka();
            k.Dodaj(1);
            k.Dodaj(2);
            k.Usun();
            k.Dodaj(3);
            while (k.Rozmiar() > 0)
            {
                Console.WriteLine(k.Usun());
            }

            Console.ReadKey();
        }
    }
}