sub average {
  map{$_[1]+=$_}@{$_[0]};$_[1]/@{$_[0]}
}

[download]
Works under strict and warnings. Although I am probably breaking your second rule (creating $_[1]).
$code or die


$ perldoc perldoc

In reply to Re: "Junkyard" Puzzle: Average of Numbers by $code or die
in thread "Junkyard" Puzzle: Average of Numbers by Masem

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