Looks like you have been well taken care of regarding your inquiry, but I would like to add a cool use of each I recently discovered. Should fit well with your code assignment. You can use each to collect the indices of an array, or both indices and values. From the docs: 
 each HASH
 each ARRAY
            When called on a hash in list context, returns a 2-element list
            consisting of the key and value for the next element of a hash. In
            Perl 5.12 and later only, it will also return the index and value
            for the next element of an array so that you can iterate over it;
            older Perls consider this a syntax error. When called in scalar
            context, returns only the key (not the value) in a hash, or the
            index in an array.
So, using each, your code can go from: 
$ perl -e '
my @colors = qw(red green blue yellow pink purple brown);
my $count = @colors;
my @drop = qw(pink brown);
my $num = 0;
foreach $num (1..$count){  
    $num--;
    if ($colors[$num] eq $drop[0] or $colors[$num] eq $drop[1]){ 
        splice (@colors, $num, 1);  
    }
}
print "@colors \n";
'

[download]
to: 
$ perl -e '
my @colors = qw(red green blue yellow pink purple brown);
my @drop = qw(pink brown);
while ( my ($num, $val) = each @colors ) {
  if ($val eq $drop[0] or $val eq $drop[1]) {
    splice (@colors, $num, 1);
  }
}
print "@colors \n";
'

[download]
both produce the following output: 
__output__
red green blue yellow purple

[download]

I hope that was the correct answer! :)

In reply to Re: The error says the value is uninitialized, but it works anyway by dbuckhal
in thread The error says the value is uninitialized, but it works anyway by mizducky

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