###
### partition-all
###

## Chapter 5 section 1.1

sub partition {
  my ($target, $treasures) = @_;
  return [] if $target == 0;
  return () if $target < 0 || @$treasures == 0;

  my ($first, @rest) = @$treasures;
  my @solutions = partition($target-$first, \@rest);
  return ((map {[$first, @$_]} @solutions), 
          partition($target, \@rest));
}