using System;

using System.Linq;

public class Program

{

​

    public void main(string[] args)

{

Action act = DoSomething();

act(); act(); act();

}

static Action DoSomething()

{

    Action ret = null;

  int n = 0;

  ret += () => Console.WriteLine(++n);

  ret += () => 

      Console.WriteLine(n++);

  return ret;

}

​

}