use strict;

my $x = 0;
my $y = 0;
my $x2 = 0;
my $y2 = 0;

if (@ARGV >= 0) { $x = shift @ARGV; }
if (@ARGV >= 0) { $y = shift @ARGV; }
if (@ARGV >= 0) { $x2 = shift @ARGV; }
if (@ARGV >= 0) { $y2 = shift @ARGV; }

print STDERR "lese Daten ...\n";

my @lines = ();
while (<STDIN>) {
   chomp $_;
   my $l = $_;
   push @lines, $l;
}

print STDERR "extrahiere Kachelbereich [$x, $y] ... [$x2, $y2]\n";

my $xstart = $x * 64;
my $ystart = $y * 64;
my $xend = $x2 * 64 + 64;
my $yend = $y2 * 64 + 64;

for (my $j = $ystart; $j < $yend && $j < @lines; $j++) {
   my @cols = split /[\s;,]/, $lines[$j];
   for (my $i = $xstart; $i < $xend && $i < @cols; $i++) {
      if ($i > $xstart) {
         print ",";
      }
      print $cols[$i];
   }
   print "\n";
}