Preserving Array Values Positions

[virtualweb]

Hello:

I have two lists of emails saved in flat files one email per line.

My script removes the emails in list 2 if they are present in list 1. Then reprints the email list, one email per line, back into list 2 but without the weeded out emails.

Except that when reprinting back to list 2 the order is random and I want to preserve the same order in which the emails were at first.

EXAMPLE:
if in email list 1 I have:

email_02@server .com
email_04@server .com
email_06@server .com
email_08@server .com
email_10@server .com

and if in email list 2 I have:

email_01@server .com
email_02@server .com
email_03@server .com
email_04@server .com
email_05@server .com
email_06@server .com
email_07@server .com
email_08@server .com
email_09@server .com
email_10@server .com

I want to end up with:

email_01@server .com
email_03@server .com
email_05@server .com
email_07@server .com
email_09@server .com

But Im getting :

email_09@server .com
email_03@server .com
email_07@server .com
email_05@server .com
email_01@server .com

Here is my script:

foreach (@All_Emails_1) {
chomp;
   
   if( /\w+@[a-zA-Z_]+?\.[a-zA-Z]{2,6}/ ){
   	$valid_emails{$_} = '1';
   	
   }
   }
foreach(@All_Emails_2){
	chomp;
	if( $valid_emails{$_} eq '1' ){
print"<B>($valid_emails{$_}) ($_)<br>";		
		delete($valid_emails{$_});
		push @repeated_emails,$_;
	}
}
my @New_All_Emails_1 = keys(%valid_emails);


$Back_Up_Emails_1 = 'All_Emails_BKUP.txt';
$Old_All_Emails_1 = 'All_Emails_1.txt';
$New_All_Emails_1 = 'All_Emails_1.txt';

rename($Old_All_Emails_1, $Back_Up_Emails_1)|| die print"Cant rename $Back_Up_Emails_1";

open (EMAILLIST, ">>$New_All_Emails_1") || die print"<br><b>Error: Cant open $New_All_Emails_1";
flock (EMAILLIST);
foreach $email @New_All_Emails_1){
print EMAILLIST "$email\n";
}
flock (EMAILLIST, 8);
close (EMAILLIST);

Thanx for your help
virtualweb

[numberwhun]

I guess my suggestion would be to do a sort:

foreach $email (sort(@New_All_Emails_1)){
    print EMAILLIST "$email\n";
}

I haven't tested it, but that should do what you want. Let us know if it works.

Regards,

Jeff

[virtualweb]

Hello numberwhun :

Thanx for your quick response.

I thought sort was used to arrange a list in a particular order. Alphabetically or from smaller to higher.

For ease of explanation I used the numerical emails 1 through 10, But emails surelly be very different in real life, and if I have emails in the follwing list:

zebra@server.co m
young@server.co m
xylophone@serve r.com
anthony@server. com

and suppose young@server.co m gets weeded out, sort would arrange my list like this:

anthony@server. com
xylophone@serve r.com
zebra@server.co m

and what I need is this: (what you might call a first comes first serve situation)

zebra@server.co m
xylophone@serve r.com
anthony@server. com

My guess is that I need to assign a number to each email prior to weeding out the repeated emails and then as you say sort the numbers and just print back the emails in an ascendent order .. but I am not good working with hashes yet.

[mohanprasadgutta]

re: Preserving Array Values Positions

Hi,

Please try this code.

use strict;
my (@list1, @list2, @new_list2);
# read from flat files
# assume @list1 is from list1.txt
open (LIST1, "list1.txt");
@list1 = <LIST1>;
close(LIST1);

# assume @list2 is from list2.txt
open (LIST2, "list2.xt");
@list2 = <LIST2>;
close(LIST2);

foreach my $email (@list2) {
   my @exists = grep { $_ eq $email } @list1;
   push @new_list2, $email unless @exists > 0;
}

# write @new_list2 to list2.txt
open(NEW_LIST2, ">list2.txt");
foreach (@new_list2) {print NEW_LIST2 $_."\n";}
close(NEW_LIST2);

Regards,
Mohan

[RonB]

#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;

my %list1;

open my $ilst1, '<', 'list1.txt' or die $!;
while (<$list1>) {
    chomp;
    $list1{$_}++;
}
close $list1;

my @filtered;
open my $list2, '<', 'list2.txt' or die $!;
while (<$list2>) {
    chomp;
    push(@filtered, $_) unless exists $list1{$_};
}
close $list2;

print Dumper \@filtered;

[numberwhun]

For your issue with hashes, try this reference.

Regards,

Jeff