public static void Main()
string[] listPositions = {"UTG", "HJ", "CO", "BU", "SB", "BB"};
string currentPosition = "CO";
int index = Array.IndexOf(listPositions, currentPosition);
string[] first = new string[6];
string[] second = new string[6];
Split(listPositions, index, out first, out second);
string[] result = second.Union(first).ToArray();
string joinList = String.Join(" ", result);
Console.WriteLine(joinList);
public static void Split<T>(T[] array, int index, out T[] first, out T[] second) {
first = array.Take(index).ToArray();
second = array.Skip(index).ToArray();