perl实现二分法的ip查找

sub search_newarea{
???? my $ip =@_[0];
???? $start=1;
???? $end=$count;
???? @ips=split(/./,$ip);
???? $long_ip =int($ips[0])*256*256*256+int($ips[1])*256*256 + int($ips[2])*256 + int($ips[3]);
???? while($start <= $end && $start >= 1 && $end <= $count){
??????????? $middle=int(($start+$end)/2);
??????????? if($long_ip>=$areas{$middle}[0] && $long_ip<=$areas{$middle}[1]){
???????????????? return $areas{$middle}[2];
??????????? }
??????????? if($long_ip>$areas{$middle}[0]){
????????????????? $start=$middle+1;
??????????? }else{
???????????????? $end=$middle-1;
??????????? }

???? }
???? return 0;
}

?

search_newarea $ip;