print ++$i;

##</code><code>##

$i = $i +1; 

print $i;

##</code><code>##

print $i++;

##</code><code>##

print $i; 

$i = $i + 1;

##</code><code>##

my @a = (1..10);

my $i = 0; 
print $a[$i++] while $i < @a;

12345678910

$i = 0; 

print $a[++$i] while $i < @a;

2345678910
Use of uninitialized value in print at (eval 8) line 1, <> line 7.