I shouldn't have used the names "@odd" and "@even", seeing as how we're supposed to be dealing with text. So here's a program which doesn't use those terribly misleading names, and deals with undefs.

#!/usr/bin/perl

use strict;
use warnings;

my @array = map{chr} ('32' .. '126');
push @array, undef, undef;
unshift @array, undef, undef, undef;

# split elements into two arrays
my (@arr0, @arr1);
while (@array > 1)
{
    my ($el0, $el1) = splice @array, 0, 2;
    push @arr0, $el0;
    push @arr1, $el1;
}

# get the last element if there is one
if(@array)
{
    push @arr0, shift @array;
}

# check that all elements were gotten
die "still elements left" if (@array);

print "arr0 = @arr0\narr1 = @arr1\n";

__END__
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