How do I get the index of the highest value in an array using LINQ?

Question

I have an array of doubles and I want the index of the highest value. These are the solutions that I\'ve come up with so far but I think that there must be a more elegant so

Answer 1

The worst possible complexity of this is O(2N) ~= O(N), but it needs to enumerate the collection two times.

 void Main()
{
    IEnumerable numbers = new int[] { 1, 2, 3, 4, 5 };

    int max = numbers.Max ();
    int index = -1;
    numbers.Any (number => { index++; return number == max;  });

    if(index != 4) {
        throw new Exception("The result should have been 4, but " + index + " was found.");
    }

    "Simple test successful.".Dump();
}