use warnings;
use strict;

use feature 'say';

say -s 'size.txt';
say -s 'empty.txt';
say -z 'size.txt';
say -z 'empty.txt';

##</code><code>##

8 # -s, 8 bytes
0 # -s, empty file
  # -z, file has bytes
1 # -z, file is empty