More info please... are there only 9 different particles, or are there lots of different kinds of particles and each cell can only hold up to nine at a time, etc.? What's your code so far? 
my @grid_a; # there are only 9 particles
my @grid_b; # there are lots of particles
for my $x (0..9) {
  for my $y (0..9) {
    for my $particle (0..8) {
      $grid_a[$x][$y][$particle] = 1;
      $grid_b[$x][$y]{$particle} = 1;
    }
    my $pcount = keys %{$grid_b[$x][$y]};
  }
}

use Data::Dumper;
print Dumper(\@grid_a, \@grid_b);

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perlreftut, perldsc

In reply to Re: Particle movement question by Anonymous Monk
in thread Particle movement question by koda123

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