in reply to are they all there?

use Array::Lookup;
my @required_items = qw(apple  orange pear);

@collections = ( [ 'apple', 'pear' ],
                 ['banana']
            );
foreach my $collection (@collections) {
    foreach my $required_item (@required_items) {
        lookup $required_item, $collection, \&notfound;
    }
}

sub notfound {
    my $required_item = shift;
    my $collection    = shift;
    push @{$collection}, $required_item;
}

foreach my $collection (@collections) {
    print "@{$collection}\n";
}

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--Artist

Replies are listed 'Best First'.
Re^2: are they all there?
by ikegami (Patriarch) on Aug 22, 2006 at 18:11 UTC

    Your solution loops {number of collections} * {number of required items} * {number of items per collection} times.

    jhourcle's solution loops {number of collections} * ( {number of items per collection} + {number of required items} ) times.

    We weren't given any numbers, but I bet your code will get execute many more times than jhourcle's, making it much slower.

    Update: Here are some very conservative sample numbers: 

    Number of collections:          5
Number of items per collection: 8
Number of items required:       10

artist:   5*8*10   = 400 iterations
jhourcle: 5*(8+10) =  90 iterations

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    Update: The OP gave some numbers. 

    Number of collections:          5  (Conservative guess.)
Number of items per collection: 12 (Middle of provided "5 to 30".)
Number of items required:       6  (Provided.)

artist:   5*12*6   = 360 iterations
jhourcle: 5*(12+6) =  90 iterations

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