Trying out an exercise that uses dereferencing Below is code and error

#! /usr/bin/perl
use v5.16.3;
use strict;
use warnings;

## 7/31/19
## program uses derefence to simplify subroutine from previous program


   sub check_required_items {
     my ($who, $items) = @_;
     my %whos_items = map { $_, 1 } @$items; # the rest are the person
+'s items

     my @required = qw(preserver sunscreen water_bottle jacket);

     for my $item (@required) {
       unless ( $whos_items{$item} ) { # not found in list 
         print "$who is missing $item, \n";
       }
     }
   }


   my @gilligan = qw(red_shirt hat lucky_socks water_bottle);
   check_required_items('gilligan', @gilligan);
   my @skipper = qw(blue_shirt hat jacket preserver sunscreen);
   my @professor = qw(sunscreen water_bottle slide_rule batteries radi
+o);
   check_required_items('skipper', @skipper);
   check_required_items('professor', @professor);

Can't use string ("red_shirt") as an ARRAY ref while "strict refs" in 
+use at ./Page_42 line 12.

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TIA The Catfish

In reply to Using Dereferencing by catfish1116

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