$ perl win.pl
PRINTING ARRAY
Use of uninitialized value in print at win.pl line 7.
abc
FOREACH
Use of uninitialized value in print at win.pl line 11.
$ cat win.pl
use strict;
use warnings;

my @array = ( 'a', 'b', undef, 'c' );

print "PRINTING ARRAY\n";
print @array, "\n";

print "FOREACH\n";
foreach( @array ) {
        print $_;
}

__END__