sub make_array($ $){
  
  my $x = ($_[0] =~ /^\d+$/) ? shift : 0;
  my $y = ($_[0] =~ /^\d+$/) ? shift : 0;

  
  my @array;
  $array[0][0] = 'X '; 
  $array[5][7] = 'X ' if (5 <= $y and 7 <= $x); 
  $array[12][15] = 'X ' if (12 <= $y and 15 <= $x); 

  
  foreach my $dy (0 .. $y){
    foreach my $dx (0 .. $x){
      (defined $array[$dy][$dx]) ? (print $array[$dy][$dx]) : (print '. ');
    }
    print "\n";
  }
}