my $s = 150; @a = 0..$s; for $r (@a) { $b[$r][$_] = $" for @a } { for $r (@a) { for (@a) { $h = 0; for $i ($r-1..$r+1) { for $j ($_-1..$_+1) { $h++ if $b[$i][$j] ne $" & $i >= 0 & $i <= $s & $j >= 0 & $j <= $s & $i ^ $r & $j ^ $_ } } $e[$r][$_] = $h == 3 ? 0 : $b[$r][$_] ne $" & $h == 2 ? 0 : $" } } print map{ @{$e[$_]}, $/ } @a; }