my ($board_size, $random_seed, $generation, @board) = (40, 10);
$\=$/;
for my $r (0..$board_size) {
 $board[$r][$_] = ! int(rand($random_seed))
 	? '*'
 	: $" for(0..$board_size)
}

sub generate {
 my ($evolved, @new_board);
 for my $r (0..$board_size) {
  for (0..$board_size) {
   my $neighbors=0;
   for my $i (-1..1) {
    for my $j (-1..1) {
     my ($neighbor_row, $neighbor_col) = ($r + $i, $_ + $j);
     next if $neighbor_row < 0 || $neighbor_row > $board_size
      || $neighbor_col < 0 || $neighbor_col > $board_size
      || !( $i || $j );
     $neighbors++
      if $board[$neighbor_row][$neighbor_col] ne $"
    }
   }
   $new_board[$r][$_] =
    ( $board[$r][$_] ne $" && $neighbors == 2 ) || $neighbors == 3
     ? '*'
     : $";
   $evolved++ if $new_board[$r][$_] ne $board[$r][$_]
  }
 }
 @board=@new_board;
 $evolved
}
do{
 print`clear`, ++$generation;
 for my $r (0..$board_size) {
  print map { $board[$r][$_] } (0..$board_size)
 }
 select $&, $&, $&, .4
} while (&generate)