@a = @ARGV;
($w, $h) = $a[0] > 2 && $a[1] > 2 ? @a : (64, 64);

$o = "P1\n$w $h\n" . "0\n" x ($w - 1);
foreach $y (1 .. $h - 2)
{
   $o .= "0\n0\n" .
         join "\n",
              map {rand() > $y / $h ? 0 : 1} (3 .. $w);
}

print $o, "0\n" x ($w + 1);