# File:	factrec.pl	
# Title: 	FACTORIAL n! RECURSIVE
#		Use subroutine.	Input from keyboard an integer.	Compute factorial
#		Do this until you want to. 	Continue(y/n)? 
# Author:	Mihaela Malita
#	 	Input number? 5
#	 	Result: 5! = 120 
#		Continue(y/n)? n
#		Bye
$yesorno = 'y';
while($yesorno eq 'y') {
	print "Input number? ";
	$n = <STDIN>;	chop($n);  #read n
	print "Result: $n ! = $r",fact($n);	  # invoke subroutine fact($n)
	print "\nContinue(y/n)? ";	#ask if more
	$yesorno = <STDIN>;	chop($yesorno);	
}
print "Bye";
exit;

sub fact {
	my($n) = @_;  #n is local variable
	if ($n == 1)   
		{return 1;}  # 1! = 1
	else  
		{return (fact($n-1) * $n );} 		# n! = n * (n-1)!
}