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

open(my $FILE, '<', 'input_file.txt') or die $!;

my %output_files;
my $line_number = 1;
while (<$FILE>)
{
	chomp;
	my @columns = split;
	my $value = abs($columns[$#columns]);
	
	if(!exists $output_files{$value})
	{
		open($output_files{$value}, '>', "test-out-$value.txt") or die $!;
	}
	my $fh = $output_files{$value};
	
	splice @columns, 0, 0, $columns[$#columns], $line_number;
	pop @columns;
	my $output_line = join "\t", @columns;
	print $fh "$output_line\n";
	
	$line_number++;
}