http://qs321.pair.com?node_id=400977


in reply to Recursion: The Towers of Hanoi problem

Here is a modified version that will display a simple ASCII representation for those people like myself that think better in pictures.
I am sure that this can be improved significantly.
Comments on where I can improve this code and what practices I should stay away from are appreciated.
This should work on both Windows and Solaris though the format may be a little off on Solaris.
#!/usr/local/bin/perl use strict; # Towers of Hanoi # Perl version (5.8.0) # Ported from Java my $numdisks = 0; my $count =0; print "Number of disks? "; chomp( $numdisks = <STDIN> ); clear (); my $i; my @polea; my @poleb; my @polec; my $loop = 0; my $string ; while ($numdisks > $loop++) { $string = $string ."x"; push (@polea, $string); push (@poleb, ""); push (@polec, ""); } print "A\tB\tC\n"; for (my $len = 0 ;$len <= ($numdisks -1); $len++) { print "$polea[$len]\t$poleb[$len]\t$polec[$len]\n"; } sleep 2; clear (); movedisks( $numdisks, 'A', 'B', 'C' ); # SUB LAND sub clear { if ($^O eq "MSWin32") { system 'cls'; }else{ system 'clear'; } } sub movedisks { my( $num, $from, $to, $aux ) = @_; if( $num == 1 ) { paintdisks ($num, $to, $from); }else{ movedisks( $num-1, $from, $aux, $to ); paintdisks ($num, $to, $from); movedisks( $num-1, $aux, $to, $from ); } } sub paintdisks { my( $num, $dest, $source) = @_; my $foo; if ($source eq "A") { $foo = $polea[0]; shift @polea; }elsif ($source eq "B") { $foo = $poleb[0]; shift @poleb; }else{ $foo = $polec[0]; shift @polec; } if ($dest eq "A") { unshift @polea, $foo; }elsif ($dest eq "B") { unshift @poleb, $foo; }else{ unshift @polec, $foo; } print "A\tB\tC\n"; for (my $len = 0 ;$len <= ($numdisks -1); $len++) { print "$polea[$len]\t$poleb[$len]\t$polec[$len]\n"; } sleep 2; clear (); }