#!/usr/bin/perl
 
use strict;
 
my $n = 25;
my $m = 16;
 
my $a = [ 0..$n-1 ];            # create list reference
 
sub foo  {
    my ($aref, @idx) = @_;      # unpack sub arguments
    foreach my $i ( @idx ) {
        $aref->[$i] = 42;       # dereference element using ->
    }
}
 
my @subarray;                   # create list
for ( my $i=0; $i < $m; $i += 2 ) {
    push @subarray, $a->[$i];   # dereference element using ->
}
 
foo($a, @subarray);             # pass list reference and list
 
print join ', ', @{ $a };       # dereference list using @{ }
 

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