{
    my $list_ref=[];

    sub gather (&){
	my $code_ref=shift;

	my @list=();
	my $safe=$list_ref;
	$list_ref=\@list;

	&$code_ref;

	$list_ref=$safe;

	return @list;
    }

    sub take  {
	push @$list_ref, @_;
	return;
    }
}

@x= gather {
     for $c (1..10){   for $b (1..$c){   for $a (1..$b){  if ( $c**2 == $b**2 + $a**2){
         take [$c,$b,$a]
     } } } }
 };
}