use strict;
use warnings;

# call as:
# full_peal( \@remaining_bells, built-up-path-in-tree )
sub full_peal
{
	my $bells_ar = shift; # @_ now contains the path so far

	if ( @$bells_ar == 0 ) # we've reached a "leaf"
	{
		local( $\, $, ) = ( "\n", " " );
		print @_; # or whatever you want to do with this permutation
		return;
	}

	# pull out each item in turn
	for my $i ( 0 .. $#{$bells_ar} )
	{
		# make a local destructable copy
		my @bells = @{$bells_ar};
		# pull out the item
		my $bell = splice @bells, $i, 1;
		# recurse, with this item added to the branch
		full_peal( \@bells, @_, $bell );
	}
}


my @bells = reverse( 1..3 ); # descending order

# begin, with an empty tree
full_peal( \@bells );