Program.cs

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

namespace c_sharp_example
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");

            List<Task<int>> l = new List<Task<int>>();
            List<int> ints = new List<int>{1, 2, 3, 4, 5};

            foreach(int i in ints)
            {
                l.Add(SleepThenReturnAsync(i)); 
            }


            newSleepMethodForReallyLongTime();

            List<int> m = new List<int>();
            foreach (Task<int> t in l)
            {
                m.Add(t.Result);
            }
            foreach (int i in m)
            {
                Console.WriteLine(i);
            }
        }

        static async Task<int> SleepThenReturnAsync(int i) 
        {
                Console.WriteLine("x: "+ i + " is sleeping");
                await Task.Delay(5000);
                return i;
       }

       static void newSleepMethodForReallyLongTime()
       {
           System.Threading.Thread.Sleep(15000);
       }

    }
}