It's not difficult to write string parsing programs. How far have you got and where are you stuck? Do you understand the requirements?
If it is to recognise mm/dd/yy, dd/mm/yy and whatever you mean by "etc", how will it know what 05/06/07 means? That could be any one of six different dates: 5th June 2007, 5th July 2006, 6th May 2007, 6th July 2005, 7th May 2006, 7th July 2006.