(Update: Verified.) The Perl 6 code for that be %hash{@array} >>++; which I think is just freaking awesome.
Jeff japhy Pinyan,
P.L., P.M., P.O.D, X.S.:
Perl,
regex,
and perlhacker How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart