Problem Statement

Select certain elements from an Array into a new Array in a generic way.

To demonstrate, select all even numbers from an Array. As an option, give a second solution which filters destructively, by modifying the original Array rather than creating a new Array.

Let's start with the solution:

my @a = (1, 2, 3, 4, 5, 6);
my @even = grep { $_%2 == 0 } @a;