A hash (associative array) is probably the way to go. Maybe something like:

my %proc_data = (
    ID1 => [qw{location1 filename1}],
    ID2 => [qw{location2 filename2}],
    ...
);
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To process your files, use something like:

for my $id (keys %proc_data) {
    my $location = $proc_data{$id}[0];
    my $filename = $proc_data{$id}[1];
    # file processing code here
}
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I strongly recommend you put the following two lines at the start of your script to get feedback on errors and possibly dangerous code:

use strict;
use warnings;
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If you have trouble understanding error or warning messages (they can be quite terse), also add:

use diagnostics;
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In addition, I'd recommend the following documentation:

• perlsyn - Perl syntax
• open - How to open files
• File::Spec - Operations on file names
• File::Copy - Moving files