public IEnumerator<string> GetEnumerator()
    {
        int firstNum;
        int secondNum;
        string currentPlayer = "first";
        int firstCardNum = 0;
        int secondCardNum = 0;
        while (true)
        {
            if (currentPlayer == "first")
            {
                firstNum = first.ElementAt(0);
                if (first.ElementAt(0) >= second.ElementAt(0))
                {
                    first.RemoveFirst();
                    currentPlayer = "second";
                    firstCardNum = 0;
                    yield return "First: " + firstNum;
                }
                else
                {
                    if (firstCardNum == first.Count)
                    {
                        yield return "Second win!";
                        yield break;
                    }
                    firstCardNum++;
                    first.RemoveFirst();
                    first.AddLast(firstNum);
                }
            }
            else
            {
                secondNum = second.ElementAt(0);
                if (second.ElementAt(0) >= first.ElementAt(0))
                {
                    second.RemoveFirst();
                    currentPlayer = "first";
                    secondCardNum = 0;
                    yield return "Second: " + secondNum;
                }
                else
                {
                    if (secondCardNum == second.Count)
                    {
                        yield return "First win!";
                        yield break;
                    }
                    secondCardNum++;
                    second.RemoveFirst();
                    second.AddLast(secondNum);
                }
            }
            if (first.Count == 0)
            {
                yield return "First win!";
                yield break;
            }
            if (second.Count == 0)
            {
                yield return "Second win!";
                yield break;
            }

        }