Alternate Weeks

[dalehopper]

Hi Guys, I am trying to display the a text value showing either Week A or Week B, the weeks don't have to be specifically set i.e we could alter them, but we run a 2 week timetable so id like week 1 to show 'A and week 2 to show 'B', or the other way around it doesn't matter.

Just wondered if this already existed or if someone could create it for me.
Many thanks
Dale