(xxx) yyy-zzzz
    +1 xxx yyy zzzz
    xxx-yyy-zzzz
    xxxyyyzzzz

##</code><code>##

    $conphone =~ tr/0-9//dc;  # remove non-digits
    if ($conphone =~ /^(\d{3})(\d{3})(\d{4})$/) {
        $conphone = $1 . '-' . $2 . '-' . $3;
    }
    else {
        print "Bad phone! No cookie!\n";
    }