That's essentially what he did. $n is uninitialized before and after the loop, but not during. This doesn't change if $n was set to a value (other than the lack of an Unitialized warning).

Output from my test (in which I changed my $n; to my $n = 255;):

Perl version is: 5.008001
50
The value of the counter after the loop is 255
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