0-0
            1-0   1-1
         2-0   2-1   2-2
      3-0   3-1   3-2   3-3
   4-0   4-1   4-2   4-3   4-4
5-0   5-1   5-2   5-3   5-4   5-5


##</code><code>##

0-0 1-0 2-0 3-1
0-0 1-0 2-1 3-1
0-0 1-1 2-1 3-1

##</code><code>##

sub enum_area{
	my ($x,$y) = split '-', $_[0];
	my $minus = $x - $y; 
	print "$_ " for grep {  
		  my ($cx,$cy) = split '-',$_; 
		  $cy > $cx  ? 0 : ( $cx-$cy < $minus + 1  ? 1 : 0)
		} 
		glob '{'.(join ',',0..$x).'}-'.
		'{'.(join ',',0..$y).'}';
	
}