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

my $inv = batch_inventory->new();

my @ranges;

for (my $c = 1; $c < 9; $c+= 3) {
  my $range = page_range->new();
  $range->{vol} = $c;
  $range->{start_pg} = $c+1;
  $range->{end_pg} = $c+2;
  push (@ranges,$range);
} 

$inv->{ranges} = @ranges;


foreach my $range ($inv->{ranges}) {
  print "$range->{vol} $range->{start_pg} $range->{end_pg}\n";
}

exit (0);

########## Objects ##########
package page_range;
sub new {
  my $class = shift;
  my $self = {
     vol => undef,
     start_pg => undef,
     end_pg => undef
  };
  bless $self, $class;
  return $self;
}

package batch_inventory;
sub new {
  my $class = shift;
  my $self = {
    ranges => undef,
    gaps => undef
  };
  bless $self, $class;
  return $self;
}