perl - Subroutine that takes average of one or more arrays -

i'm working on subroutine takes average of 1 or more arrays. without using module.

use strict; use warnings;  use list::util 'sum';  @w = (0, 2); @x = (1, 3); @y = (2, 2); @z = (1, 1);  # average of these 4 arrays (1,2) since # (0+1+2+1)/4 = 1 , (2+3+2+1)/4 = 2      @arrays = \(@w, @x, @y, @z);  @avg; # way using module $i (0..$#w) {     $avg[$i] =  sum(map $_->[$i], @arrays) / @arrays; } print "@avg\n";  # way of doing without module @avg; $i (0..$#w) {     $avg[$i] = prod_sum(map $_->[$i], \@arrays) / @arrays; }  print "@avg\n";   # subroutines sub prod_sum{     $o = $_[0];     $arr_ref = $_[1];     $array_ref;      foreach $row (@$arr_ref){         foreach $cell (@$row) {             push(@{ $array_ref }, $_);         }     }      $sum = $o + the_sum($array_ref);     return $sum; }  sub the_sum{     $sum = 0;     ( @{$_[0]} ) {         $sum += $_;     }     return $sum; } 

output

1 2 [pair of random big numbers] 

the first output correct. displays average of of arrays. second output wrong. how do without using module?

i propose solution:

use strict; use warnings;  @w = (0, 2); @x = (1, 3); @y = (2, 2); @z = (1, 1);  @arrays = \(@w, @x, @y, @z);  ($x, $y) = (0, 0); foreach $arr(@arrays) {     $x += $arr->[0];     $y += $arr->[1]; }  @result = ( $x / @arrays,  $y / @arrays);  print "(@result)", "\n";  # <---- prints (1 2)