Adding Days To YYYYMMDD Date Format

Zoomie has asked for the wisdom of the Perl Monks concerning the following question:

Hi All,

I hope you can help me wrie a subroutine to add a number of days to a date in the yyyymmdd format.

I want to add x days to it.

Example:

20120516 + 24 = 20120609

Thanks for your help...