#!/usr/bin/perl
#use strict;
open(FILE1,"C:/Perl/BX/BX-Users.txt");
open(FILE2,"C:/Perl/BX/BX-Book-Ratings.txt");
open(result1,">C:/perl/BX/BX-Users_result.txt");
my $i=0;
my $j=0;
while((my $bxUser=<FILE1>)&&($i<10))
{
	my $userId=substr($bxUser,0,index($bxUser,","));
	while(my $rankUser=<FILE2>)
	{
		my $userIdCmp=substr($rankUser,0,index($rankUser,","));
		if(($userId==$userIdCmp)&&($j==0))
		{
			syswrite(result1,"$bxUser");
			$j++;
		}

	}
	$j=0;
	$i++;
	
}
close(FILE1);
close(FILE2);
close(result1);