Re: Closed geometry: a train track problem

[Anonymous Monk]

Hi
You might want to take a look at the code of a game called "MAZE". It works with a 2 dimentional map, keeps track of your current position and gives you valid directions to make it through the MAZE. Maybe this gives you a good insperation.

Here is a copy of it:

#!/usr/bin/perl -w
use strict;

my @maze=(
      [ qw( e   swe we ws  ) ],
      [ qw( se new sw ns ) ],
      [ qw( ns  -      ns n  ) ],
      [ qw( ne w     ne w   ) ],
   );

my %direction=( n=> [ -1, 0], s=> [1,  0],
   e=> [  0, 1], w=> [0, -1]);
my %full=( e => 'East', n => 'North', w=>'West', s=>'South');
my($curr_x, $curr_y, $x, $y)=(0,0,3,3);
my $move;

sub disp_location {
    my($cx, $cy)=@_;
    print "You may move ";
    while($maze[$cx][$cy]=~/([nsew])/g) {
         print "$full{$1} ";
    }

    print "($maze[$cx][$cy])\n";
}

sub move_to {
    my($new, $xref, $yref)=@_;
    $new=substr(lc($new),0,1);
    if ($maze[$$xref][$$yref]!~/$new/) {
       print "Invalid direction, $new.\n";
       return;
    }
    $$xref += $direction{$new}[0];
    $$yref += $direction{$new}[1];
}

until ( $curr_x == $x and $curr_y == $y ) {
    disp_location($curr_x, $curr_y);
    print "Which way? ";
    $move=<STDIN>; chomp $move;
    exit if ($move=~/^q/);
    move_to($move, \$curr_x, \$curr_y);
}

print "You made it through the maze!\n";

(Provided by "SAMS Teach yourself Perl in 24 Hours")

Good luck!
Marcel

200604 Janitored by Corion: Added formatting