#!/usr/bin/perl
use strict;
use warnings;
use 5.016;

chomp (my @data_lines = <DATA>);

# Sort the data lines according to the "Company Name" field and then the "Invoice ID" field.
@data_lines = sort {
    my ($company_name_a, $invoice_ID_a) = (split /\t/, $a)[1, 0];
    my ($company_name_b, $invoice_ID_b) = (split /\t/, $b)[1, 0];
    fc($company_name_a) cmp fc($company_name_b)
        or $invoice_ID_a <=> $invoice_ID_b
} @data_lines;

print "$_\n" for @data_lines;

__DATA__
1	SEBASTIAN COMMUNICATIONS
2	MASQUE SOUND
3	SEALEVEL SYSTEMS
4	MASSTECH, INC
5	SE INTERNATIONAL
6	SOUTHEAST SERVO, LLC
7	SEALEVEL SYSTEMS, INC.
8	MASTERBILT