$a=1;
while($a>=-1){
  $b=-2;
  while($b<1){
    $c='X';
    $d=$b;
    $e=$a;
    for(1..50){
      $g=$d;
      $d=$d**2-$e**2+$b;
      $e=2*$g*$e+$a;
      $c=' 'if$d**2+$e**2>4;
    }
    print$c;
    $b+=0.05;
  }
  print"\n";
  $a-=0.1;
}