I have a hash in my main code that I wish to bring into a subroutine, modify and then return to print the data values.

Problem: I can't get the modified hash to return to the main code properly. When I try to print a hash value in my code I get the value from the original hash, and not the modified one. Or, I get a warning that the hash reference is undefined.

Here's an example I made of my problem using Star Trek references - I wish to replace the values in the hash (%starship) with different numbers if I find a match for the captain's name in the variable ($captains) input into the subroutine (trivia).

use strict;
use warnings;

my $captains = "kirkpicard";
my %starship = (
    'EntTOS'=>0, 'EntA'=>0, 'EntD'=>0, 'EntE'=>0,
    );

trivia ($captains,\%starship);

print "Kirk was on Enterprise #:   $starship{EntTOS}, $starship{EntA}\
+n";
print "Picard was on Enterprise #: $starship{EntD}, $starship{EntE}\n"
+;

sub trivia {,
     my ($captains, $starship_ref) = shift;
     %starship = %{$starship_ref};
      
     if ($captains =~ m/(kirk)/) {

         $starship {'EntTOS'} = 1;
         $starship {'EntA'} = 2;

     }

     if ($captains =~ m/(picard)/) {

          $starship {'EntD'} = 4;
          $starship {'EntE'} = 5;
     }
     return %starship;
}

[download]

The output I should get is as follows:

Kirk was on Enterprise #: 1, 2
  Picard was on Enterprise #:4, 5

[download]

Any ideas how to make it so?

In reply to Replacing original hash with modified hash returned from subroutine by CommaSplice

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