my @sorted= @_; #using shift didn't work, why? format?

##</code><code>##

use strict;
use warnings;
use autodie;
use Data::Dump qw(dump);
 

open my $in, '<', 'numbers.txt' or die $!;

    my @data =split/\s+/,<$in>;
    close $in;

my ($mean,$ref,@new_sort)= sort_num(@data);
my $length=$$ref; #passing by ref example
#print "sorted : @new_sort\n";
print "mean : $mean\n";
print "length : $length\n";


my ($middle,$median)=median_num(@new_sort);
print "this is median : $median\n";
print "this will be middle num position : $middle\n";

my ($size,$hash_ref)=mode_num( {NUMBERS=>\@new_sort} ); #
my $true_size=$$size;
print "this is length :$true_size\n";
foreach my $k (keys %$hash_ref){
    for (0..$length){
    print " $hash_ref->{$k}[$_]"; #%hash->NUMBER=> i_number #there are undef but dump doesn't show these
     }
    }
    
      
# my sub practice with ref and hash_ref
sub sort_num{
    our @sorted=sort {$a <=> $b}@_;
    our $length = scalar (@sorted);
    our $add_div_elem =(eval join '+',@sorted)/$length;
   median_num(\@sorted);
   return $add_div_elem,\$length,@sorted;
    }
    
 sub median_num{
     my @sorted= @_; #using shift didn't work, why? format?
     my $middle_one = eval ((scalar @sorted)+ 1)/2;
     my $median=$sorted[$middle_one];
     return ( $middle_one, $median)#
     } 
     
   #passing by references
 sub mode_num{
      my %opt =  %{shift @_ } ; #creating hash
      my $size=keys %opt->{NUMBERS}; #getting size of hash
      #my %count=();
      #for (0..$size){
         #have to defined the hash coz perl will see 0 if undef
          #   foreach my $key ( keys %opt->{$key}){
          #   my $value= $opt->{$key}[$_];
           #  if (not exists $count{$value}){
           #      $count{$value}=[];
            #     }
           #  push $count{$value},$key;
            # }
       
       #}
  return \$size,\%opt;
   }