一个计算数组长度的perl脚本

#!/usr/bin/perl
#edit www.jb200.com
open(FILE1,"C:/Perl/BX/BX-Book-Ratings_result.txt");
open(FILE2,"C:/Perl/BX/BX-Users_result.txt");
open(result1,">C:/Perl/BX/BX-Book-Ratings_short.txt");
open(result2,">C:/Perl/BX/BX-Users_short.txt");
 
my @ISBN;
my $isbnNum=0;
my $i=0;
my $user;
my $subString;
my $count=0;
 
while(($_=<FILE1>)&&($user=<FILE2>))
{
    $subString=substr($_,index($_,",")+1);
    @ISBN=split(/ /,$subString);
    $isbnNum=scalar(@ISBN);
    if($isbnNum>4)
    {
        syswrite(result1,"$_");
        syswrite(result2,"$user");
        $count++;
    }
    else
    {
        next;
    }
    #printf"@ISBN $isbnNum $user";
    #$i++;
        
}
printf"$count";
close(FILE1);
close(FILE2);
close(result1);
close(result2);