#!/usr/bin/perl  
use strict;  
use warnings;  
use List::Util qw/ max /;  
  
my @matrix;  
my $path = '.'; # (current directory - '.') or path to data files  
  
my @file = qw/list.txt one.txt another.txt/;  
  
for my $file ( @file ) {  
	my %data;  
	my @substrate;  
  
	open my $fh, "<", "$path/$file"  
		or die "Unable to open $file for reading. $!";  
  
	while (<$fh>) {  
		if (/^substrate/) {  
			@substrate = /\d+/g;  
		}  
		elsif (/^product/) {  
			while (/(\d+)/g) {  
				for my $sub (@substrate) {  
					$data{$sub}{$1} = 1 ;  
				}  
			}  
		}  
		else {  
			die "Unknown format $file. $!";	  
		}  
	}  
	close $fh or die "Unable to close $file. $!";  
  
	print "Processing file: $file\n";  
	process(%data);  
  
	push @matrix, \%data;  
}  
  
for my $i (0 .. $#matrix) {  
	for my $j ($i+1 .. $#matrix) {  
		print "Combining $file[$i] and $file[$j]\n";  
		my %data = combine($matrix[$i], $matrix[$j]);  
		process(%data);  
	}	  
}  
  
sub process {  
	my %data = @_;  
	my %seen;  
  
	my @product = sort {$a <=> $b}  
				  grep ! $seen{$_}++,  
				  map keys %$_, values %data;  
  
	# to get column width for print  
	my $wid = 1 + max map length, @product;  
  
	printf "%7s" . "%${wid}s" x @product . "\n", 'prod->', @product;  
  
	for my $substrate (sort {$a <=> $b} keys %data) {  
	    printf "%7s", $substrate;  
	    printf "%${wid}s", $data{$substrate}{$_} || '-' for @product;  
	    print "\n";  
	}  
	printf "\n%5s\n%5s\n%s\n\n", '^', '|', 'substrate';  
}  
  
  
sub combine {  
	my ($matrix1, $matrix2) = @_;  
	my %new_hash = %$matrix1;  
  
	for my $substrate (keys %$matrix2) {  
		$new_hash{$substrate}{$_} = 1 for keys %{ $matrix2->{$substrate} };	  
	}  
	return %new_hash;  
}