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%h = qw[ a 2 b 4 c 2 d 1 e 1 f 2 g 4 h 3 ];; ... pp \%f;; { 1 => 2, 2 => 3, 3 => 1, 4 => 2 }
$f2{ $_ } = 0 for 0 .. 5;; ... pp \%f2;; { "0" => 0, 1 => 2, 2 => 3, 3 => 1, 4 => 2, 5 => 0 }