You're looking for the number of elements in the intersection between the two arrays. You're looking for this: 
my %x; $x{$_} = undef for @selected_data;
my %y; $y{$_} = undef for @all_data;
my $total;
foreach my $k ( keys %x ) {
    $total++ if exists $y{$k};
}
print "Count -> $total\n";

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My criteria for good software:
  1. Does it work?
  2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

In reply to Re: Can I get better approach to get solution by dragonchild
in thread Can I get better approach to get solution by Anonymous Monk

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