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CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
					
public class Program
{
	public static void Main()
	{
		Console.WriteLine(CommaQuibblify(new string[] { }));
        Console.WriteLine(CommaQuibblify(new string[] { "ABC" }));
        Console.WriteLine(CommaQuibblify(new string[] { "ABC", "DEF" }));
        Console.WriteLine(CommaQuibblify(new string[] { "ABC", "DEF", "G", "H" }));
	}
	
	public static string CommaQuibblify(IEnumerable<string> items)
	{
		var head = string.Join(", ", items.SkipLast(2).Append(""));
		var tail = string.Join(" and ", items.TakeLast(2));
		return '{' + head + tail + '}';
	}
}