( reverse keys %upload )[ -19 .. 0 ]

That's not going to do what you think unless there are exactly 20 keys.

my @array = 1 .. 40; 
print $_ for @array[-19 .. 0];

[download]

Also, by grepping the defined elements out of your 20 element slice, you risk having less than 20 elements to work with. You probably want to grep the defined elements first and then work with the appropriate 20 element slice.

-sauoq
"My two cents aren't worth a dime.";

In reply to Re: Re: Re: mathematical equation by sauoq
in thread mathematical equation by Anonymous Monk

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