open(OUT,'>'.$fil) or die $!;
binmode OUT;
for $i(1 .. 10000){
 $lat=int(rand(20000))+440000;
 $lon=int(rand(10000))+20000;
 $typ=chr(31);
 $cod=pack('l>l>C',$lat,$lon,$typ);
 print OUT $cod;
}
close(OUT);

##</code><code>##

$lah=pack('l>',$lah);
$lab=pack('l>',$lab);
$loh=pack('l>',$loh);
$lob=pack('l>',$lob);
open(IN,"<ch";
@fil=stat(IN);
$num=$fil[7]/9;
binmode(IN);
for(1 .. $num){
 read(IN,$lat,4);
 read(IN,$lon,4);
 read(IN,$pyt,1);
 if(($lat lt $lah) && ($lat gt $lab) && ($lon lt $loh) && ($lon gt $lob)){
  print "OK";
 }
}