Given: A list of data items of all the same type (call this @l), and a subroutine c() that takes in that data type and returns either 1 or 0 if the item should be removed or not, respectively.

Find: The perl golf lines necessary to not only produce array @r, the list of items that are removed, but to also to remove those items from @l itself (or at least, to have @l contain items from @a that were not in @r). Order must be maintained in both arrays. Assume that 'use strict' is in play, and you certainly may use additional variables. If you need a test case, use @r=(0..25), with sub c { (($_[0] % 3) == 0); } (e.g. remove multiples of 3).

Update: There's an easy way to do this by going through the list twice. However, for a harder challenge assume that the results of c() may depend on the time when processed, and thus, you only want to evaluate c() once for each item on the original list. (And thanks tye for updates.)

Dr. Michael K. Neylon - mneylon-pm@masemware.com || "You've left the lens cap of your mind on again, Pinky" - The Brain

In reply to Golf: List spliting by Masem

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