use strict;
use warnings;
my ($i, $j) = @ARGV;
my $acker = ackermann($i, $j);
print "A($i,$j) = $acker\n";
my $iter = 0;
sub ackermann{
	$iter ++;
	my $i = shift;
	my $j = shift;
	print "Iteration $iter: i = $i, j = $j \n";
	return if $iter >= 40;
	if($i == 1){
		undef $i;
		return 2**$j;
	}
	elsif($j==1){
		undef $j;
		return ackermann($i-1,2);
	}
	else{
		return ackermann($i-1, ackermann($i,$j-1));
	} 
}