How do you find the maximum element index?

[jeanid]

Got a list.

var lst = new List<double>();
lst.Add(123);
lst.Add(123);
lst.Add(2);

I'm trying to get a maximum element index, but I can't figure out how to get the last maximum element back. At the moment, he says that the maximum element 0, which is in principle true, but I need the maximum final index.

public int MaxIndex<T>(IEnumerable<T> source)
        {
            IComparer<T> comparer = Comparer<T>.Default;
            using (var iterator = source.GetEnumerator())
            {
                if (!iterator.MoveNext())
                {
                    throw new InvalidOperationException("Empty sequence");
                }
                int maxIndex = 0;
                T maxElement = iterator.Current;
                int index = 0;
                while (iterator.MoveNext())
                {
                    index++;
                    T element = iterator.Current;
                    if (comparer.Compare(element, maxElement) > 0)
                    {
                        maxElement = element;
                        maxIndex = index;
                    }
                }
                return maxIndex;
            }
        }

[inna]

using System.Linq;
...
lst.LastIndexOf(lst.Max());