Combinations - generate

static List<string[]> GenerateCombinations(string[] elements, int N)
        {
            List<string[]> combinations = new List<string[]>();
            GenerateCombinationsRecursive(elements, N, 0, new string[N], combinations);
            return combinations;
        }

        static void GenerateCombinationsRecursive(string[] elements, int N, int startIndex, string[] currentCombination, List<string[]> combinations)
        {
            if (N == 0)
            {
                combinations.Add((string[])currentCombination.Clone());
                return;
            }

            for (int i = startIndex; i < elements.Length; i++)
            {
                currentCombination[currentCombination.Length - N] = elements[i];
                GenerateCombinationsRecursive(elements, N - 1, i + 1, currentCombination, combinations);
            }
        }