perl 计算数组长度

计算数组长度函数scalar;

有代码有真相：

#!/usr/bin/perl
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);