The lines 
my @arr1 = @{$r1};
my @arr2 = @{$r2};

[download]
are derefencing the array references, and making copies of them. You are then in turn modifying the local copy of the array.
Modifying it using 
$r2->[1] = "q";

[download]
should do the trick.

Update: $$r2[1] = "q"; will also work. It is your preference.

In reply to Re: Array references inside a subroutine by tcf22
in thread Array references inside a subroutine by Anonymous Monk

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