Hi All, I'm a Perl beginner trying to do something very basic and encountering an issue. I want to find how many times each item in an array appears in a separate .txt document - when an item doesn't appear an error message should be printed. I have cobbled together the code below from various sources and it seemed to work at first glance, but the script only counts one instance of each item. 

@ids = ("a", "b", "c", "d", "e", "f", "g",);

my %counts;

foreach my $id (@ids)
{
open(FILE, "list.txt" ) || die "couldn't open 2\n";
$/ = undef;

while (<FILE>) {
    if (/$id/g) {

        $counts{$id}++;
        }
        
        else { 
        
        print "$id not found\n";
        
        }
        
}

close FILE;
}

  use Data::Dumper;
  print Dumper \%counts;

[download]
Sorry I can't work out how to include the contents of list.txt into the above code - I've included it below instead 
a
b
b
c
c
d
d
d
f
f
f

[download]

This script returns: 

e not found
g not found
$VAR1 = {
          'f' => 1,
          'c' => 1,
          'b' => 1,
          'd' => 1,
          'a' => 1
        };

[download]
When I'm expecting: 
e not found
g not found
$VAR1 = {
          'f' => 3,
          'c' => 2,
          'b' => 2,
          'd' => 3,
          'a' => 1
        };

[download]

My uneducated guess is that it is the way I am reading in list.txt that is 'wiping' the hash, but unfortuantely I have no idea how to fix it. Any tips would be very much appreciated. Thank you in advance!

In reply to Perl beginner's issue with hash by Maire

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