use strict;
use warnings;

my $area = 800;
my $pre = 555;
my $not = 9999;

$_ = join '', <DATA>;
print "$area-$pre-$1\n" while m/$area(?:\)?\s|\.|-)$pre[\s\.-]((?!9999)\d{4})/g;

__DATA__
1-800-555-9999
1-800-555-3456
(800) 555-3456
800 555 3456
800 555-3456
800.555.3456
800
555.5555