use Data::Dumper;

sub sub1{

    for $x (0 .. 100){
	$array[$x] = 0;
    }
# omit the part for generating the array;

    return \@array;
}

####################### main part
my $index;

for ($index=0; $index<2; $index++){
    $arr_ref = &sub1($index);
    $arr[$index] = @$arr_ref;

    die Dumper(\@arr);

    foreach (0 .. 100){
	print "$arr[$index][$_]\n";
    }
}

##</code><code>##

$VAR1 = [
          101
        ];

##</code><code>##

sub sub1{

    my @array;

    for $x (0 .. 100){
        $array[$x] = 0;
    }
# omit the part for generating the array;

    return \@array;
}