foreach my $checked (@chk_acc) 
     {
       chomp();

##</code><code>##

       if($checked=~/^(\w{3})(\d{4,7})/ig)
        {
          # it should print the accounts starting with letters here

##</code><code>##

       if ( $checked =~ /^[[:alpha:]]{3}\d{4,7}/ )
        {
          # it should print the accounts starting with letters here