my $Number_of_geographical_regions = 4;

my $Number_of_generations = 3;


##</code><code>##


Generation 1:
Geographical regions: 
2
3
1
4

Generation 2:
Geographical regions: 
4
2
3
1

Generation 3:
Geographical regions: 
1
4
3
2
<br>


##</code><code>##


my $nregions = 354;   # 354;
my $number_of_replicates = 3;

my %seen;

foreach my $generation (1..$number_of_replicates) {  ##  TEMP
  my @members = random_subset_X($nregions, $nregions );#$number_of_replicates ); # 5 element subsets, e.g.  ####  THIS BIT NEEDS SORTING OUT
  my $key = join(" ", @members); # note: members already sorted
  redo if $seen{$key}; # make sure the subsets are unique
  $seen{$key} = 1;
  print "\n\nI'm about to enter the insert subset subroutine\n\n";
  insert_subset($generation, @members);
}      ##  TEMP


sub random_subset_X {
  my ($n, $k) = @_; # $k member subset of 1..$n.   # # $n is no. of regions, $k no. of replicates
  my %member;
  while ($k > 0) {
    my $x = int(rand()*$n)+1; # generates random number 1..$n.
    redo if $member{$x};
    $member{$x} = 1;
    $k--;
  } continue {
    $k--;
  }
  sort keys %member;
}



sub insert_subset {
  my ( $generation, @members) = @_;
  for my $x (@members) {
  #  $sth_insert_into_random->execute($generation, $x);
    print "$generation\t$x\n";
  }
}