Is boiler-plate code required for challenges? [duplicate]

Question

When solving a puzzle with an appropriate solution, does the programming language standard boiler-plate source code need to be included:

For example, should I include all of this:

using System;
using System.Linq;

public class Program
{
    public static void Main()
    {
        Console.WriteLine("Code Golfing Is My Favourite Sport!");
    }
}

Alternatively, is it enough to include the actual specific code which solves the challenge, i.e.:

Console.WriteLine("Code Golfing Is My Favourite Sport!");