in reply to Array Comparison

That nested loop is the killer. How about a hash? The following code is untested and unoptimized but performs better algorithmically:

my %exclude;
@exclude{ @exclude } = ();

my @cleaned = grep { exists $exclude{ $_ } ? () : $_ } @words;

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Update: Yep, I confused grep with map in my pre-breakfast haste. That should rather be:

my @cleaned = grep { ! exists $exclude{ $_ } } @words;

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Re: Re: Array Comparison
by Roy Johnson (Monsignor) on Dec 22, 2003 at 18:37 UTC
    I think that should be 
    my @cleaned = grep { not exists $exclude{$_} } @words;

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    Grep returns the original value for every element for which the expression returns true. Your ternary operator would be useful in map, but not here.
    The PerlMonk tr/// Advocate
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[d/l]
      Excellent, this works much faster.

      Now, if I can just sort and make the list with just unique entries, I'm all set. Thanks.

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        my @uniq = sort keys %{{map {$_ => 1} @cleaned}};

        [download]
        or you could combine two statements in one (not recommended though :-) ...
        my @uniq = sort keys %{{map {$_ => 1}
                        grep{not exists $exclude{$_}}@words}};

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[d/l]
[select]

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