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CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;
using System.Linq;

public class Program
{
	private static readonly Random _r = new Random();
	private static IEnumerable<(T, T)> FunkyLotto<T>(IEnumerable<T> source)
	{
		var pool = source.ToList();
		var iteration = pool.ToList();
		foreach (var item in iteration)
		{
			int choice;
			if (pool.Count == 2 && pool.IndexOf(item) >= 0) // special case when there is only 2 left, and there is a case for a duplicate
				choice = (pool.IndexOf(item) + 1) % pool.Count;
			else
				choice = _r.Next(0, pool.Count);
			choice = Equals(item, pool[choice]) ? (choice + 1) % pool.Count : choice;
			yield return (item, pool[choice]);
			pool.RemoveAt(choice);
		}
	}

	public static void Main()
	{
		var list = new[]{"Joe", "John", "Chris", "Henry", "Tom", "Patrick"};
		foreach (var result in FunkyLotto(list))
			Console.WriteLine(result);
	}
}