#!C:\perl\bin
use strict;
#use warnings;      # commented out because it throws a warning in the middle
#use diagnostics;   # of execution, about @polea being uninitialized. ??

# Towers of Hanoi
# Perl version (5.10.0)

my $numdisks = 0;
my $count = 0;
my $grandTotal = 0;

print "Number of disks? ";
chomp( $numdisks = <STDIN> );
clear ();

my $i = 0;
my @polea = "";
my @poleb = "";
my @polec = "";
my $loop = 0;
my $string = "";
while ($numdisks > $loop++) {
    $string = $string ."x";
    push (@polea, $string);
}
print "A\t\t\tB\t\t\tC\n";
for (my $len = 0 ;$len <= $numdisks; $len++) {
    print "$polea[$len]\t\t\t$poleb[$len]\t\t\t$polec[$len]\n";
}

sleep 1;
movedisks( $numdisks, 'A', 'B', 'C' );
print "Total: ", $grandTotal, " \n";

# 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( $numb, $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\t\t\tB\t\t\tC\n";
    for (my $len = 0 ;$len <= ($numdisks -1); $len++) {
        print "$polea[$len]\t\t\t$poleb[$len]\t\t\t$polec[$len]\n";
    }
    $grandTotal ++;
    sleep 1;
#    clear ();  commented out so I can see the execution!
}

##</code><code>##

Results of execution:
Number of Disks: 3

A                       B                       C

x
xx
xxx
A                       B                       C
x
xx
xxx
A                       B                       C
xx                                              x
xxx

A                       B                       C
xx                                                 << here it pushes a space!
xxx                                             x

A                       B                       C
xxx                     xx
                                                x

A                       B                       C
   << same here         xx                      x
xxx

A                       B                       C
                        x
xxx                     xx

A                       B                       C
xxx                      << again here
                        x
                        xx
Total: 7

# I'm at a loss
#
# Result that appears when use warnings & use diagnostics are uncommented
#

A                       B                       C

Use of uninitialized value in concatenation (.) or string at towers2.pl line
        29, <STDIN> line 1 (#1)
    (W uninitialized) An undefined value was used as if it were already
    defined.  It was interpreted as a "" or a 0, but maybe it was a mistake.
    To suppress this warning assign a defined value to your variables.

    To help you figure out what was undefined, perl will try to tell you the
    name of the variable (if any) that was undefined. In some cases it cannot
    do this, so it also tells you what operation you used the undefined value
    in.  Note, however, that perl optimizes your program and the operation
    displayed in the warning may not necessarily appear literally in your
    program.  For example, "that $foo" is usually optimized into "that "
    . $foo, and the warning will refer to the concatenation (.) operator,
    even though there is no . in your program.

x
xx
xxx
A                       B                       C
x
Use of uninitialized value in concatenation (.) or string at towers2.pl line
        79, <STDIN> line 1 (#1)
xx
xxx
A                       B                       C
xx                                              x
xxx
Use of uninitialized value within @polea in concatenation (.) or string at
        towers2.pl line 79, <STDIN> line 1 (#1)

A                       B                       C
xx
xxx                                             x

A                       B                       C
xxx                     xx
                                                x

A                       B                       C
                        xx                      x
xxx

A                       B                       C
                        x
xxx                     xx

A                       B                       C
xxx
                        x
                        xx
Total: 7

##</code><code>##

C:\Perl\working>perl towers2.pl
Not enough arguments for map at towers2.pl line 32, near """)"
Global symbol "$polea" requires explicit package name at towers2.pl line 32.
Global symbol "$poleb" requires explicit package name at towers2.pl line 32.
Global symbol "$polec" requires explicit package name at towers2.pl line 32.
Global symbol "$polea" requires explicit package name at towers2.pl line 84.
Global symbol "$poleb" requires explicit package name at towers2.pl line 84.
Global symbol "$polec" requires explicit package name at towers2.pl line 84.
Execution of towers2.pl aborted due to compilation errors (#1)
    (F) The function requires more arguments than you specified.

Uncaught exception from user code:
        Not enough arguments for map at towers2.pl line 32, near """)"
Global symbol "$polea" requires explicit package name at towers2.pl line 32.
Global symbol "$poleb" requires explicit package name at towers2.pl line 32.
Global symbol "$polec" requires explicit package name at towers2.pl line 32.
Global symbol "$polea" requires explicit package name at towers2.pl line 84.
Global symbol "$poleb" requires explicit package name at towers2.pl line 84.
Global symbol "$polec" requires explicit package name at towers2.pl line 84.
Execution of towers2.pl aborted due to compilation errors.
 at towers2.pl line 91
##</code><code>##

my $i = 0;
#my @polea;  #This was conflicting with the map initialization below
my @poleb;
my @polec;
my $loop = 0;
my $string = "";
#while ($numdisks > $loop++) {
#    $string = $string ."x";
#    push (@polea, $string);
#}
my @polea = map 'x' x $_, 1 .. $numdisks;

print "A\t\t\tB\t\t\tC\n";
for (my $len = 0 ;$len <= $numdisks; $len++) {
#    print "$polea[$len]\t\t\t$poleb[$len]\t\t\t$polec[$len]\n";
32  print join "\t\t\t", map ($_->[$len] || ""), \$polea, \$poleb, \$polec;
    print "\n";
}

##</code><code>##

    print join "\t\t\t", map {[$_]->[$len] || ""} \my $polea, \my $poleb, \my $polec;
    print "\n";

##</code><code>##


A                       B                       C
                        x
SCALAR(0x183ce7c)                       SCALAR(0x183ceac)
SCALAR(0x183cecc)
                        xx

                        xxx

                        xxxx

                        xxxxx


Total Moves: 31