#! perl -slw
use strict;
use constant 	ALLPRODUCTS	=>0;
use constant	PROHIBITED	=>1;

my @allProducts = map { int rand 10_000 } 1..1000;
my @selection = map { $allProducts[rand 1000] } 1..50;

sub randProduct (\@\@) {
	local $"="\cA"; #!"
	my ($choice, $disallowed) = ('', "@{$_[PROHIBITED]}");
	$choice = $_[ALLPRODUCTS]->[rand @{$_[ALLPRODUCTS]}] while 1+index( $disallowed, $choice );
	return $choice;
}

my $chosen = randProduct @allProducts, @selection;