use warnings;
use strict;

my $ndisks = 3;
hanoi( $ndisks, 'A', 'C', 'B', 0 );

sub hanoi 
{
        my( $n, $start, $end, $extra, $depth ) = @_;

        print "\t"x$depth . "n=$n, start=$start end=$end extra=$extra\n";

        if( $n == 1 )
        {
                print "\t"x$depth . "Move disk #$n from $start to $end\n";
        }
        else
        {
                $depth++;
                print "\t"x$depth . "Calling hanoi 1\n";
                hanoi( $n-1, $start, $extra, $end, $depth);
                print "\t"x$depth . "Move disk #$n from $start to $end\n";
                print "\t"x$depth . "Calling hanoi 2\n";
                hanoi ($n-1, $extra, $end, $start, $depth);
        }
}