Hello Monks,

In the code below, I pass the array @num as a reference to the subroutine second. At second, the array is changed and some value (not directly related to the array) is returned to the calling sub. I want to preserve the value of the original array @num after the operation at second. What is the best way to do that? 

use strict;

my @num = qw(1 2 3 4 5);

first();

sub first {
   print "\@num before: @num\n";
   # prints 1 2 3 4 5
   my $result = second(\@num);
   print "result: $result\n";
   print "\@num after: @num\n";
   # prints 1 2 3 4 5 6
   # But I would need it to still print
   # 1 2 3 4 5
}

sub second {
   my $num_ref = shift;

   push(@$num_ref, 6);

   my $sum = 0;

   foreach (@$num_ref) {
      $sum += $_;
   }

   return $sum;
}

[download]
Thank you so much.

In reply to Preserve the value of original array by Anonymous Monk

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