use strict;     #<--****
use warnings;     #<---***

##</code><code>##

$main::x = 10;
print $main::x, "\n";  #10

##</code><code>##


use vars qw{$x};
print $x, "\n";  #10

##</code><code>##

# $y = 'hello';  #error under use strict
our $y = 'hello';
print $y, "\n";  #hello

##</code><code>##

{
    our $z = 5;
    print $z, "\n";  #5
}

# print $z, "\n";  #error
print $main::z, "\n";  #5

{
    use vars qw{$s};
    $s = 'bye';

    print $s, "\n";  #bye
}

print $s, "\n";  #bye