using System;

using System.Threading;

using System.Threading.Tasks;

public class Program

{

    static async Task Main()

    {

        Console.WriteLine("Hello World");

        Task<int>[] tasks = new Task<int>[3];

        tasks[0] = Test();

        tasks[1] = Test();

        tasks[2] = Test();

        foreach (var t in tasks)

        {

            Console.WriteLine("executing task");

            var res = await t;

            Console.WriteLine("done");

        }

    }

    static async Task<int> Test()

    {

        var task =  Task.Delay(2000);

        Console.WriteLine("create task");

        await task;

        Console.WriteLine("finish task");

        return 1;

    }

}