perlmeditation Masem In light of [id://79027|Junkward Wars, Perl Style], I offer the following puzzle which limits what you have to work with. <P> In this case, your task is to write a subroutine that takes in a reference to a list of numbers and returns the average of those numbers, with the limitations that: <UL> <LI>You cannot modify the array elements themselves, or if you do, the array must be restored to it's original state before the subroutine is over. <LI>You may not declare or use any other variables outside of what perl 'provides' to you. For example, you have to use @_ at some point to get the array, but perl provides this due to the nature of subroutines. You may also use variables like $_ when inside a map/grep/for block, or the use of $1, $2, etc in regex statements when these have been created for you. However, you may not use $_ or any other of the reserved perl variables outside of these types of blocks. <LI>You cannot use an external module, nor a system command; the calculation should be done entire by perl itself and not call on any other programs. </UL> <HR> <I> Dr. Michael K. Neylon - <a href="mailto:mneylon-pm@masemware.com">mneylon-pm@masemware.com</a> || "You've left the lens cap of your mind on again, Pinky" - The Brain </I>