15 lines
207 B
Plaintext
15 lines
207 B
Plaintext
|
|
|
|
###
|
|
### factorial1
|
|
###
|
|
|
|
## Chapter 5 section 4.2
|
|
|
|
sub factorial {
|
|
my ($n, $product) = @_;
|
|
$product = 1 unless defined $product;
|
|
return $product if $n == 0;
|
|
return factorial($n-1, $n * $product);
|
|
}
|